By means of in situ diffuse reflectance FTIR, the IR spectra of 6 coals with different ranks were obtained from room temperature to 230 ℃. A new curve fitting method was used to recognize the different hydrogen ...By means of in situ diffuse reflectance FTIR, the IR spectra of 6 coals with different ranks were obtained from room temperature to 230 ℃. A new curve fitting method was used to recognize the different hydrogen bonds in the coals, and the influence of coal ranks on the distribution of hydrogen bonds(HBs) in the coals and their thermal stability were discussed. The results show that there is another new HB(around 2514 cm -1 ) between the -SH in mercaptans or thiophenols and the nitrogen in the pyridine like compounds in the coals, and the evidence for that was provided. The controversial band of the HB between hydroxyl and the nitrogen of the pyridine like compounds was determined in the range of 3028-2984 cm -1 , and the result is consistent with but more specific than that of Painter et al .. It was found that the stability of different HBs in the coals is influenced by both coal rank and temperature. For some HBs, the higher the coal rank, the higher the stability of them. Within the temperature range of our research, the stability of the HB between the hydroxyl and the π bond increases to some extent for some coals at temperatures higher than 110 or 140 ℃.展开更多
Co-crystallization of pztcH_4 with 4,4'-bipyridine(4,4'-bipy) in pH = 3-4 and 1-2 gave two new binary molecular adducts: [(4,4'-bipy H2)(pztc H2)](1) and [(4,4'-bipy H2)(pztcH3)(Cl)]·4H2O(2),...Co-crystallization of pztcH_4 with 4,4'-bipyridine(4,4'-bipy) in pH = 3-4 and 1-2 gave two new binary molecular adducts: [(4,4'-bipy H2)(pztc H2)](1) and [(4,4'-bipy H2)(pztcH3)(Cl)]·4H2O(2), respectively. Compounds 1 and 2 have been characterized by IR, elemental analysis, NMR and X-ray single-crystal diffraction. Compound 1 crystallizes in triclinic, space group P1 with a = 5.7752(12), b = 7.9126(16), c = 9.4492(19) ?, α = 97.49(3), β = 107.71(3), γ = 94.52(3)o, V = 404.62(14) A^3, Z = 1, μ = 0.137 mm^1, Dc = 1.692 Mg/m^3, C18H12N4O8, Mr = 412.32, F(000) = 212, S = 1.025, R = 0.0360 and wR = 0.0973. Compound 2 crystallizes in monoclinic, space group C2/c with a = 17.093(3), b = 7.7665(16), c = 18.414(4) A, β = 113.36(3)o, V = 2244.1(8) A^3, Z = 4, μ = 0.244 mm^-1, Dc = 1.542 Mg/m^3, C18H21ClN4O12, Mr = 520.84, F(000) = 1080, S = 1.021, R = 0.0343 and wR = 0.0978. In compound 1, pztc H22- anions self-formed 2-D sheets by strong Oacid-H···Oacidhydrogen bonds, which are further extended to form a 3-D supramolecular network bridged with 4,4?-bipy via N-H···Oacid interactions. In compound 2, besides the 1-D chain constructed by pztc H3-itself through strong H-bond Oacid-H···Oacid, the other chain is constructed with 4,4?-bipy H22+, Cl-anion and water molecules by moderate H-bonds and Ow-H···Cl and N-H···Ow. The two chains are linked with μ3-connected water molecules resulting from the combination of strong synthon-assisted H-bonding Oacid-H···Ow to afford an interlaced 3-D network.展开更多
Two zinc(Ⅱ) compounds, [Zn(L)(H2O)2]n 1 and [Zn(4,4'-bpy)(H2O)4](L) 2 (H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid), were synthesized by hydrothermal methods and characterized by single-cryst...Two zinc(Ⅱ) compounds, [Zn(L)(H2O)2]n 1 and [Zn(4,4'-bpy)(H2O)4](L) 2 (H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid), were synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction analyses. Compound 1 crystallizes in monoclinic, space group C2/c with a=15.4970(16), b = 5.4976(6), c = 10.7113(12) A, β=96.298(6)°, C6H8O6Zn, Mr = 241.50, V = 907.06(17) A^3, Z = 4, D, = 1.768 g/cm^3, F(000) = 488,μ = 2.703 mm^-1, S = 1.060, the final R = 0.0256 and wR = 0.0660 for 968 observed reflections with Ⅰ 〉 2σ(Ⅰ). Compound 2 crystallizes in triclinic, space group P1^- with a = 6.915(2), b = 7.166(2), c = 10.363(3) A, α = 73.250(4), β = 84.429(4), γ = 61.605(3)°, C16H2ON2O8Zn, Mr = 433.70, V = 432.1 (2) A^3, Z = 1, D, = 1.667 g/cm^3, F(000) = 224 and μ= 1.471 mm^-1, S = 1.118, the final R = 0.0486 and wR = 0.1077 for 1352 observed reflections with Ⅰ〉 2σ(Ⅰ). Upon using the assembly strategy of combination of coordination polymer chains with intermolecular hydrogen bonds, three-dimensional frameworks of complexes 1 and 2 were formed.展开更多
Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific...Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been investigated.These environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation processes.We quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics separation.This article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic perspective.Results showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing heteroaromatics.Imidazolium ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical tests.Therefore,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.展开更多
The concept of resonance-assisted hydrogen bonds(RAHBs)highlights the synergistic interplay between theπ-resonance and hydrogen bonding interactions.This concept has been well-accepted in academia and is widely used ...The concept of resonance-assisted hydrogen bonds(RAHBs)highlights the synergistic interplay between theπ-resonance and hydrogen bonding interactions.This concept has been well-accepted in academia and is widely used in practice.However,it has been argued that the seemingly enhanced intramolecular hydrogen bonding(IMHB)in unsaturated compounds may simply be a result of the constraints imposed by theσ-skeleton framework.Thus,it is crucial to estimate the strength of IMHBs.In this work,we used two approaches to probe the resonance effect and estimate the strength of the IMHBs in the two exemplary cases of the enol forms of acetylacetone and o-hydroxyacetophenone.One approach is the block-localized wavefunction(BLW)method,which is a variant of the ab initio valence bond(VB)theory.Using this approach,it is possible to derive the geometries and energetics with resonance shut down.The other approach is Edmiston’s truncated localized molecular orbital(TLMO)technique,which monitors the energy changes by removing the delocalization tails from localized molecular orbitals.The integrated BLW and TLMO studies confirmed that the hydrogen bonding in these two molecules is indeed enhanced byπ-resonance,and that this enhancement is not a result ofσconstraints.展开更多
To probe the behavior of hydrogen bonds in solid energetic materials, we conduct ReaxFF and SCC-DFTB molecular dynamics simulations of crystalline TATB, RDX, and DATB. By comparing the intra- and inter-molecular hydro...To probe the behavior of hydrogen bonds in solid energetic materials, we conduct ReaxFF and SCC-DFTB molecular dynamics simulations of crystalline TATB, RDX, and DATB. By comparing the intra- and inter-molecular hydrogen bond- ing rates, we find that the crystal structures are stabilized by inter-molecular hydrogen bond networks. Under high-pressure, the inter- and intra-molecular hydrogen bonds in solid TATB and DATB are nearly equivalent. The hydrogen bonds in solid TATB and DATB are much shorter than in solid RDX, which suggests strong hydrogen bond interactions existing in these energetic materials. Stretching of the C-H bond is observed in solid RDX, which may lead to further decomposition and even detonation.展开更多
Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a...Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a lack of efficient tools that accurately predict DES formation.The search for DES relies heavily on intuition or trial-and-error processes,leading to low success rates or missed opportunities.Recognizing that hydrogen bonds(HBs)play a central role in DES formation,we aim to identify HB features that distinguish DES from non-DES systems and use them to develop machine learning(ML)models to discover new DES systems.We first analyze the HB properties of 38 known DES and 111 known non-DES systems using their molecular dynamics(MD)simulation trajectories.The analysis reveals that DES systems have two unique features compared to non-DES systems:The DESs have①more imbalance between the numbers of the two intra-component HBs and②more and stronger inter-component HBs.Based on these results,we develop 30 ML models using ten algorithms and three types of HB-based descriptors.The model performance is first benchmarked using the average and minimal receiver operating characteristic(ROC)-area under the curve(AUC)values.We also analyze the importance of individual features in the models,and the results are consistent with the simulation-based statistical analysis.Finally,we validate the models using the experimental data of 34 systems.The extra trees forest model outperforms the other models in the validation,with an ROC-AUC of 0.88.Our work illustrates the importance of HBs in DES formation and shows the potential of ML in discovering new DESs.展开更多
Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(...Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature treatment.This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate.Specifi cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to Pd.The interfacial sites exhibit a synergistic adsorption eff ect on the reaction substrate.Pd^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption sites.This synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated intermediate.As a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.展开更多
Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic batteries.Herein,a high-performance quinone-based polymer(H-PNADB...Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic batteries.Herein,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)strategy.The intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in theory.In situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current densities.Specifically,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular HB.This work provides an efficient approach toward insoluble organic electrode materials.展开更多
Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structu...Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.展开更多
The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulat...The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulating the structural chemistry of EDL via the introduction of intermolecular hydrogen bonds has been proposed(p-hydroxybenzoic acid(pHA)is selected as proof-of-concept).According to the molecular dynamics(MD)simulation and density functional theory(DFT)calculation results,the existence of hydrogen bonds realizes the anion structural rearrangement in the EDL,reduces the lowest unoccupied molecular orbital(LUMO)energy level of anions in the EDL,and the number of free solvent molecules,which promotes the formation of inorganic species-enriched SEI and eventually achieves the dendrite-free Li deposition.Based on this strategy,Li‖Cu cells can stably run over 185 cycles with an accumulated active Li loss of only 2.27 mAh cm^(-2),and the long-term cycle stability of Li‖Li cells is increased to 1200 h.In addition,the full cell pairing with the commercial LiFePO_(4)(LFP)cathodes exhibits stable cycling performance at 1C,with a capacity retention close to 90%after 200 cycles.展开更多
The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) io...The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) ions in OIHMHs is primarily confined to the low energy region,resulting in yellow or red emissions.To date,there are few reports about green emission of Sb^(3+)-doped OIHMHs.Here,we present a novel approach for regulating the luminescence of Sb^(3+) ions in 0D C_(10)H_(2)_(2)N_(6)InCl_(7)·H_(2)O via hydrogen bond network,in which water molecules act as agents for hydrogen bonding.Sb^(3+)-doped C_(10)H_(2)2N_(6)InCl_(7)·H_(2)O shows a broadband green emission peaking at 540 nm and a high photoluminescence quantum yield(PLQY)of 80%.It is found that the intense green emission stems from the radiative recombination of the self-trapped excitons(STEs).Upon removal of water molecules with heat,C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7) generates yellow emis-sion,attributed to the breaking of the hydrogen bond network and large structural distortions of excited state.Once water molecules are adsorbed by C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7),it can subsequently emit green light.This water-induced reversible emission switching is successfully used for optical security and information encryption.Our findings expand the under-standing of how the local coordination structure influences the photophysical mechanism in Sb^(3+)-doped metal halides and provide a novel method to control the STEs emission.展开更多
Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and mole...Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and molecular characteristics,often posing challenges for precise diagnoses using conventional methods.To this end,this study aimed to identify the novel variants responsible for GPI deficiency in a Chinese family.Methods:The clinical manifestations of the patient were summarized and analyzed for GPI deficiency phenotype diagnosis.Novel compound heterozygous variants of the GPI gene,c.174C>A(p.Asn58Lys)and c.1538G>T(p.Trp513Leu),were identified using whole-exome and Sanger sequencing.The AlphaFold program and Chimera software were used to analyze the effects of compound heterozygous variants on GPI structure.Results:By characterizing 53 GPI missense/nonsense variants from previous literature and two novel missense variants identified in this study,we found that most variants were located in exons 3,4,12,and 18,with a few localized in exons 8,9,and 14.This study identified novel compound heterozygous variants associated with GPI deficiency.These pathogenic variants disrupt hydrogen bonds formed by highly conserved GPI amino acids.Conclusion:Early family-based sequencing analyses,especially for patients with congenital anemia,can help increase diagnostic accuracy for GPI deficiency,improve child healthcare,and enable genetic counseling.展开更多
A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2(2H2O (H2L = 3-nitrophthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The com...A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2(2H2O (H2L = 3-nitrophthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P1^- with a = 8.1549(16), b = 8.8856(18), c = 15.277(3)A,α= 100.93(3),α= 90.81(3), γ= 104.56(3)°, V = 1049.8(4)A^3, Z = 1,μ= 2.125 mm^-1, Dc=1.994 g/cm^3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3+ ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La^3+ ion is nine-coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C-H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially.展开更多
The solvothermal reaction of CuI with 5-amino-2-benzimidazolethiol in acetonitrile condition affords complex [Cuz(5-amino-2-benzimidazolethiol)2]2 which has been characterized by elemental analysis, infrared spectru...The solvothermal reaction of CuI with 5-amino-2-benzimidazolethiol in acetonitrile condition affords complex [Cuz(5-amino-2-benzimidazolethiol)2]2 which has been characterized by elemental analysis, infrared spectrum and single-crystal X-ray diffraction analysis. Crystal data for C28H24N12S4Cu4: monoclinic, space group C2/c with a = 15.970(5), b = 12.365(4), c = 16.293(5) A, fl = 91.977(6)°, V = 3215.5(18), Z = 4, Mr= 910.99, Dc= 1.882 g/cm3 , F(000) = 1824, p = 2.913 mm-1, λ(MoKa) = 0.71073A, T= 293(2) K, the final R = 0.0527 and wR = 0.1342. X-ray diffraction analysis revealed that the title complex exhibits a l D channel constructed from tetranuclear-copper(I) motifs connected by hydrogen bonds and shows strong photoluminescence in the solid state at room temperature.展开更多
A new coordination polymer, {[Cd(OPY)(tdc)(HO)]·H2 O}n(OPY = 4,4?-(oxybis(4,1-phenylene))dipyridine, H2 tdc = thiophene-2,5-dicarboxylic acid), has been synthesized hydrothermally based on a V-shaped ligand OPY. ...A new coordination polymer, {[Cd(OPY)(tdc)(HO)]·H2 O}n(OPY = 4,4?-(oxybis(4,1-phenylene))dipyridine, H2 tdc = thiophene-2,5-dicarboxylic acid), has been synthesized hydrothermally based on a V-shaped ligand OPY. The structure was fully characterized by elemental analysis, FT-IR spectroscopy, and X-ray single-crystal diffraction analysis. In1, two OPY ligands and one water molecule acted as terminal ligands coordinating to Cdcation to form [Cd(OPY)HO]units, which are then linked by tdc2-ligands to generate a one-dimensional chain. Every two adjacent chains linked by extensive O–H···O hydrogen bonds constitute one-dimensional double-chains, and such chains are extended into two-dimensional layers via O–H···N hydrogen bonds. These layers are further connected to form a three-dimensional supramolecular architecture via π-π stacking interactions. In addition, the thermal stability and solid state fluorescence property of 1 were also investigated.展开更多
A two-dimensional hydrogen-bonded cadmium(II) compound [Cd(dapm)2- (CH3COO)2(H2O)2] (dapm = diaminodiphenylmethane) has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes ...A two-dimensional hydrogen-bonded cadmium(II) compound [Cd(dapm)2- (CH3COO)2(H2O)2] (dapm = diaminodiphenylmethane) has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group C2/c with a = 27.572(3), b = 5.5064(5), c = 23.310(2) , = 124.785(1)o, C15H19Cdo.5ON2O3, Mr =331.52, V = 2906.6(5) ?, Z = 4, Dc = 1.515 g/cm3, F(000) = 1368 and = 0.801 mm-1. The final R = 0.0403 and wR = 0.1014 for 1795 observed reflections with I≥4(I). The centrosymmetric Cd(II) is six- coordinated in a distorted octahedral geometry, and the dapm in a trans mode acts as a monoden- tate ligand. The intermolecular hydrogen bonds among coordinated aqua molecules with coordi- nated acetate oxygen atoms and uncoordinated dapm nitrogen atoms form a two-dimensional supramolecular framework.展开更多
The assembly of 1,4-benzenedicarboxylic acid (H2bdc), 4,4?bipyridine (4,4?bipy), trimethyltin chloride and MnBr24H2O in hydrothermal conditions gave rise to a hydrogen-bonded three-dimensional complex {[Mn(4,4?bipy)4H...The assembly of 1,4-benzenedicarboxylic acid (H2bdc), 4,4?bipyridine (4,4?bipy), trimethyltin chloride and MnBr24H2O in hydrothermal conditions gave rise to a hydrogen-bonded three-dimensional complex {[Mn(4,4?bipy)4H2O](bdc)}n which has been characterized by single- crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P2/n with a = 7.0001(2), b = 11.5540(3), c = 11.4192(1) ? = 101.754(2)? V = 904.21(4) 3, Z = 2, C18H20MnN2O8, Mr = 447.30, Dc = 1.643 g/cm3, F(000) = 462 and m(MoK? = 0.783 mm-1. The final R and wR are 0.0499 and 0.1301, respectively for 1335 observed reflections with I ≥ 2(I). The Mn (Ⅱ) is six-coordinated in a distorted octahedral geometry. 4,4?Bipyridine in a m-bridge mode links [Mn(H2O)4]2+ into a linear cation chain. bdc acts as a counter anion and links the linear chains into a three-dimensional structure through hydrogen bonds.展开更多
The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = ...The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = 0.93 cm-1 and F(000) = 504.00. The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I > 2s(I)), respectively. The dihedral angle between the two phenyl rings is 52.9 and that between the NO2 group and its attached ring is 3.0. In the crystal, molecules are stacked along [100] through p…p interactions. The CH…O hydrogen bond (3.403 ? 120.4? laterally connects the stacks along [010] to form networks (001) which are further anti- parallelly connected by CH…O (3.382 ? 142.9) and p…p interactions extending along [001]. Also presented here is a brief study on the CH…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types, namely, )5(12R, )4(21R, )8(22R, )6(12R and )7(22R, with the first three occurring more often.展开更多
1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea, C15H10F4N2OS, has been synthesized firstly and determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system...1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea, C15H10F4N2OS, has been synthesized firstly and determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group C2/c with a = 31.87(3), b = 7.705(9), c = 12.591(14) A°, b = 106.06(2)°, V = 2971(6) A°^3, Z = 8, Dc=1.530 g·cm^-1, F(000) = 1392, m = 0.266 mm^–1, S = 1.06, the final R = 0.070 and w R(I 〉 2s(I)) = 0.249. The crystal structure revealed that the carbonyl thiourea unit in the determined compound was mostly planar due in part to the formation of intramolecular N–H···O=C and C–H···S=C hydrogen bonds that form two S(6) rings. The intermolecular contacts of the crystal structure have been preformed based on the Hirshfeld surface and their associated 2D fingerprint plots. In the packing diagram of the synthesized compound, the C=S group formed two types of intermolecular hydrogen bonds by the H–N(C=O) group and the H–C of the phenyl ring, respectively, and they formed R2^2(8) and R2^2(14) ring motifs, respectively. The crystal packing form was also stabilized by the intermolecular hydrogen bonds C–H···O(1–x, y, 0.5–z) with the R2^2(10) ring motifs. In addition, supramolecular layers sustained by π-π stacking interactions(between the C(2)~C(7) rings with the C(10)~C(15) rings) are formed in the crystal structure of the title compound. The electronic and reactivity were assessed by the natural bond orbital(NBO) analysis in this study.展开更多
基金Supported by the National Natural Science Foundation of China(No.2 990 6 0 12)
文摘By means of in situ diffuse reflectance FTIR, the IR spectra of 6 coals with different ranks were obtained from room temperature to 230 ℃. A new curve fitting method was used to recognize the different hydrogen bonds in the coals, and the influence of coal ranks on the distribution of hydrogen bonds(HBs) in the coals and their thermal stability were discussed. The results show that there is another new HB(around 2514 cm -1 ) between the -SH in mercaptans or thiophenols and the nitrogen in the pyridine like compounds in the coals, and the evidence for that was provided. The controversial band of the HB between hydroxyl and the nitrogen of the pyridine like compounds was determined in the range of 3028-2984 cm -1 , and the result is consistent with but more specific than that of Painter et al .. It was found that the stability of different HBs in the coals is influenced by both coal rank and temperature. For some HBs, the higher the coal rank, the higher the stability of them. Within the temperature range of our research, the stability of the HB between the hydroxyl and the π bond increases to some extent for some coals at temperatures higher than 110 or 140 ℃.
基金supported by the National Natural Science Foundation of China(No.21571094)
文摘Co-crystallization of pztcH_4 with 4,4'-bipyridine(4,4'-bipy) in pH = 3-4 and 1-2 gave two new binary molecular adducts: [(4,4'-bipy H2)(pztc H2)](1) and [(4,4'-bipy H2)(pztcH3)(Cl)]·4H2O(2), respectively. Compounds 1 and 2 have been characterized by IR, elemental analysis, NMR and X-ray single-crystal diffraction. Compound 1 crystallizes in triclinic, space group P1 with a = 5.7752(12), b = 7.9126(16), c = 9.4492(19) ?, α = 97.49(3), β = 107.71(3), γ = 94.52(3)o, V = 404.62(14) A^3, Z = 1, μ = 0.137 mm^1, Dc = 1.692 Mg/m^3, C18H12N4O8, Mr = 412.32, F(000) = 212, S = 1.025, R = 0.0360 and wR = 0.0973. Compound 2 crystallizes in monoclinic, space group C2/c with a = 17.093(3), b = 7.7665(16), c = 18.414(4) A, β = 113.36(3)o, V = 2244.1(8) A^3, Z = 4, μ = 0.244 mm^-1, Dc = 1.542 Mg/m^3, C18H21ClN4O12, Mr = 520.84, F(000) = 1080, S = 1.021, R = 0.0343 and wR = 0.0978. In compound 1, pztc H22- anions self-formed 2-D sheets by strong Oacid-H···Oacidhydrogen bonds, which are further extended to form a 3-D supramolecular network bridged with 4,4?-bipy via N-H···Oacid interactions. In compound 2, besides the 1-D chain constructed by pztc H3-itself through strong H-bond Oacid-H···Oacid, the other chain is constructed with 4,4?-bipy H22+, Cl-anion and water molecules by moderate H-bonds and Ow-H···Cl and N-H···Ow. The two chains are linked with μ3-connected water molecules resulting from the combination of strong synthon-assisted H-bonding Oacid-H···Ow to afford an interlaced 3-D network.
基金This work was supported by the National Natural Science Foundation of China (No. 20231020)
文摘Two zinc(Ⅱ) compounds, [Zn(L)(H2O)2]n 1 and [Zn(4,4'-bpy)(H2O)4](L) 2 (H2L = trans,trans-1,3 butadiene 1,4-dicarboxylic acid), were synthesized by hydrothermal methods and characterized by single-crystal X-ray diffraction analyses. Compound 1 crystallizes in monoclinic, space group C2/c with a=15.4970(16), b = 5.4976(6), c = 10.7113(12) A, β=96.298(6)°, C6H8O6Zn, Mr = 241.50, V = 907.06(17) A^3, Z = 4, D, = 1.768 g/cm^3, F(000) = 488,μ = 2.703 mm^-1, S = 1.060, the final R = 0.0256 and wR = 0.0660 for 968 observed reflections with Ⅰ 〉 2σ(Ⅰ). Compound 2 crystallizes in triclinic, space group P1^- with a = 6.915(2), b = 7.166(2), c = 10.363(3) A, α = 73.250(4), β = 84.429(4), γ = 61.605(3)°, C16H2ON2O8Zn, Mr = 433.70, V = 432.1 (2) A^3, Z = 1, D, = 1.667 g/cm^3, F(000) = 224 and μ= 1.471 mm^-1, S = 1.118, the final R = 0.0486 and wR = 0.1077 for 1352 observed reflections with Ⅰ〉 2σ(Ⅰ). Upon using the assembly strategy of combination of coordination polymer chains with intermolecular hydrogen bonds, three-dimensional frameworks of complexes 1 and 2 were formed.
基金support from the National Natural Science Foundation of China(22038008)the science and technology innovation project of China Shenhua Coal to Liquid and Chemical Company Limited(MZYHG-2021-01).
文摘Focusing on the use of imidazolium ionic liquids and quaternary ammonium salts-based deep eutectic solvents for the separation of phenols and nitrogen-containing heteroaromatics,the role of heteroaromatics as specific sites for hydrogen bond-based separation has been investigated.These environmentally friendly solvents are known for their ability to form hydrogen bonds with heteroatoms,a key aspect in separation processes.We quantified the hydrogen bond interaction energy to reach the threshold energy for efficient O-and N-heteroaromatics separation.This article provides an in-depth study of the structural nuances of different hydrogen bonding sites and their affinity properties while conducting a comparative evaluation of the separation efficiency of ionic liquids and deep eutectic solvents from a thermodynamic perspective.Results showed that phenols with dual hydrogen bonding recognition sites were easier to separate than nitrogen-containing heteroaromatics.Imidazolium ionic liquids were more suitable for the extraction of nonbasic nitrogen-containing heteroaromatics,and quaternary ammonium salts-based deep eutectic solvents are more effective for phenols and basic nitrogen-containing heteroaromatics,which was confirmed by Fourier transform infrared spectroscopy and empirical tests.Therefore,this study provides a theoretical basis for the strategy design and selection of extractants for the efficient separation of O-and N-containing aromatic compounds.
文摘The concept of resonance-assisted hydrogen bonds(RAHBs)highlights the synergistic interplay between theπ-resonance and hydrogen bonding interactions.This concept has been well-accepted in academia and is widely used in practice.However,it has been argued that the seemingly enhanced intramolecular hydrogen bonding(IMHB)in unsaturated compounds may simply be a result of the constraints imposed by theσ-skeleton framework.Thus,it is crucial to estimate the strength of IMHBs.In this work,we used two approaches to probe the resonance effect and estimate the strength of the IMHBs in the two exemplary cases of the enol forms of acetylacetone and o-hydroxyacetophenone.One approach is the block-localized wavefunction(BLW)method,which is a variant of the ab initio valence bond(VB)theory.Using this approach,it is possible to derive the geometries and energetics with resonance shut down.The other approach is Edmiston’s truncated localized molecular orbital(TLMO)technique,which monitors the energy changes by removing the delocalization tails from localized molecular orbitals.The integrated BLW and TLMO studies confirmed that the hydrogen bonding in these two molecules is indeed enhanced byπ-resonance,and that this enhancement is not a result ofσconstraints.
基金Project supported by the National Natural Science Foundation of China(Grant No.11176020)the Fund from the China Academy of Engineering Physics,China(Grant No.2011A0302014)
文摘To probe the behavior of hydrogen bonds in solid energetic materials, we conduct ReaxFF and SCC-DFTB molecular dynamics simulations of crystalline TATB, RDX, and DATB. By comparing the intra- and inter-molecular hydrogen bond- ing rates, we find that the crystal structures are stabilized by inter-molecular hydrogen bond networks. Under high-pressure, the inter- and intra-molecular hydrogen bonds in solid TATB and DATB are nearly equivalent. The hydrogen bonds in solid TATB and DATB are much shorter than in solid RDX, which suggests strong hydrogen bond interactions existing in these energetic materials. Stretching of the C-H bond is observed in solid RDX, which may lead to further decomposition and even detonation.
基金supported by Ignite Research Collaborations(IRC),Startup funds,and the UK Artificial Intelligence(AI)in Medicine Research Alliance Pilot(NCATS UL1TR001998 and NCI P30 CA177558)。
文摘Non-ionic deep eutectic solvents(DESs)are non-ionic designer solvents with various applications in catalysis,extraction,carbon capture,and pharmaceuticals.However,discovering new DES candidates is challenging due to a lack of efficient tools that accurately predict DES formation.The search for DES relies heavily on intuition or trial-and-error processes,leading to low success rates or missed opportunities.Recognizing that hydrogen bonds(HBs)play a central role in DES formation,we aim to identify HB features that distinguish DES from non-DES systems and use them to develop machine learning(ML)models to discover new DES systems.We first analyze the HB properties of 38 known DES and 111 known non-DES systems using their molecular dynamics(MD)simulation trajectories.The analysis reveals that DES systems have two unique features compared to non-DES systems:The DESs have①more imbalance between the numbers of the two intra-component HBs and②more and stronger inter-component HBs.Based on these results,we develop 30 ML models using ten algorithms and three types of HB-based descriptors.The model performance is first benchmarked using the average and minimal receiver operating characteristic(ROC)-area under the curve(AUC)values.We also analyze the importance of individual features in the models,and the results are consistent with the simulation-based statistical analysis.Finally,we validate the models using the experimental data of 34 systems.The extra trees forest model outperforms the other models in the validation,with an ROC-AUC of 0.88.Our work illustrates the importance of HBs in DES formation and shows the potential of ML in discovering new DESs.
基金This work was supported by the National Key Research and Development Program of China(No.2023YFB4203800).
文摘Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups(e.g.,C=C and C=O)is a promising yet challenging endeavor.In our study,we developed a Pd/CeO_(2) catalyst by enhancing the oxygen vacancy(O V)concentration in CeO_(2) through high-temperature treatment.This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate.Specifi cally,metal Pd^(0) atoms bonded to the O V in defective CeO_(2) formed Pd^(0)-O v-Ce^(3+)interfacial sites,enabling strong electron transfer from CeO_(2) to Pd.The interfacial sites exhibit a synergistic adsorption eff ect on the reaction substrate.Pd^(0) sites promote the adsorption and activation of C=C bonds,while O V preferably adsorbs C=O bonds,mitigating competition with C=C bonds for Pd^(0) adsorption sites.This synergy ensures rapid C=C bond activation and accelerates the attack of active H*species on the semi-hydrogenated intermediate.As a result,our Pd/CeO_(2)-500 catalyst,enriched with Pd^(0)-O v-Ce^(3+)interfacial sites,dem-onstrated excellent hydrogenation activity at just 30℃.The catalyst achieved a Cis-C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·g metal).This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts.
基金supported by the National Natural Science Foundation of China (22279063 and 52001170)the Fundamental Research Funds for the Central Universities+2 种基金Tianjin Natural Science Foundation (No. 22JCYBJC00590)the financial support by the Ministry of Education, Singapore, under its Academic Research Fund Tier 1 Thematic (RT8/22)the Haihe Laboratory of Sustainable Chemical Transformations, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) for financial support
文摘Organic compounds have the advantages of green sustainability and high designability,but their high solubility leads to poor durability of zinc-organic batteries.Herein,a high-performance quinone-based polymer(H-PNADBQ)material is designed by introducing an intramolecular hydrogen bonding(HB)strategy.The intramolecular HB(C=O⋯N-H)is formed in the reaction of 1,4-benzoquinone and 1,5-naphthalene diamine,which efficiently reduces the H-PNADBQ solubility and enhances its charge transfer in theory.In situ ultraviolet-visible analysis further reveals the insolubility of H-PNADBQ during the electrochemical cycles,enabling high durability at different current densities.Specifically,the H-PNADBQ electrode with high loading(10 mg cm^(-2))performs a long cycling life at 125 mA g^(-1)(>290 cycles).The H-PNADBQ also shows high rate capability(137.1 mAh g^(−1)at 25 A g^(−1))due to significantly improved kinetics inducted by intramolecular HB.This work provides an efficient approach toward insoluble organic electrode materials.
基金The Project was supported by State Key Project of Basic Research MOST G1998061307 the National Natural Science Foundation of China (NSFC+8 种基金 grant No. 59733060 59873030 59953001 59903008 29671002 39730160 20023005 29901002) and Major Proj
文摘Based on cryogenic FT-IR spectroscopic studies of hydrogen bonds in cholic acid, two-dimensional FT-IR spectroscopy was applied to enhance our understanding of the hydrogen bonds of cholic acid. Fine spectral structures were revealed by asynchronous 2D FT-IR spectra. The co-relationship among various bands was discussed according to the synchronous 2D FT-IR spectrum.
基金financially supported by the National Natural Science Foundation of China(Grant No.21905033,52271201)the Key Research and DevelopmentProgram of Sichuan Province(Grant No.2022YFG0100)+1 种基金the Central Government Funds of Guiding Local Scientific and Technological Development for Sichuan Province(Grant No.2022ZYD0045)the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization(Grant No.2020P4FZG02A)
文摘The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulating the structural chemistry of EDL via the introduction of intermolecular hydrogen bonds has been proposed(p-hydroxybenzoic acid(pHA)is selected as proof-of-concept).According to the molecular dynamics(MD)simulation and density functional theory(DFT)calculation results,the existence of hydrogen bonds realizes the anion structural rearrangement in the EDL,reduces the lowest unoccupied molecular orbital(LUMO)energy level of anions in the EDL,and the number of free solvent molecules,which promotes the formation of inorganic species-enriched SEI and eventually achieves the dendrite-free Li deposition.Based on this strategy,Li‖Cu cells can stably run over 185 cycles with an accumulated active Li loss of only 2.27 mAh cm^(-2),and the long-term cycle stability of Li‖Li cells is increased to 1200 h.In addition,the full cell pairing with the commercial LiFePO_(4)(LFP)cathodes exhibits stable cycling performance at 1C,with a capacity retention close to 90%after 200 cycles.
基金National Natural Science Foundation of China(11974063)Graduate research innovation project,School of Optoelectronic Engineering,Chongqing University(GDYKC2023002)+1 种基金Fundamental Research Funds for the Central Universities(2022CDJQY-010)The authors extend their appreciation to the Deputyship for Research and Innovation,Ministry of Education in Saudi Arabia for funding this research work through the project no.(IFKSUOR3-073-9).
文摘The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) ions in OIHMHs is primarily confined to the low energy region,resulting in yellow or red emissions.To date,there are few reports about green emission of Sb^(3+)-doped OIHMHs.Here,we present a novel approach for regulating the luminescence of Sb^(3+) ions in 0D C_(10)H_(2)_(2)N_(6)InCl_(7)·H_(2)O via hydrogen bond network,in which water molecules act as agents for hydrogen bonding.Sb^(3+)-doped C_(10)H_(2)2N_(6)InCl_(7)·H_(2)O shows a broadband green emission peaking at 540 nm and a high photoluminescence quantum yield(PLQY)of 80%.It is found that the intense green emission stems from the radiative recombination of the self-trapped excitons(STEs).Upon removal of water molecules with heat,C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7) generates yellow emis-sion,attributed to the breaking of the hydrogen bond network and large structural distortions of excited state.Once water molecules are adsorbed by C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7),it can subsequently emit green light.This water-induced reversible emission switching is successfully used for optical security and information encryption.Our findings expand the under-standing of how the local coordination structure influences the photophysical mechanism in Sb^(3+)-doped metal halides and provide a novel method to control the STEs emission.
文摘Objective:Glucose-6-phosphate isomerase(GPI)deficiency is a rare hereditary nonspherocytic hemolytic anemia caused by GPI gene variants.This disorder exhibits wide heterogeneity in its clinical manifestations and molecular characteristics,often posing challenges for precise diagnoses using conventional methods.To this end,this study aimed to identify the novel variants responsible for GPI deficiency in a Chinese family.Methods:The clinical manifestations of the patient were summarized and analyzed for GPI deficiency phenotype diagnosis.Novel compound heterozygous variants of the GPI gene,c.174C>A(p.Asn58Lys)and c.1538G>T(p.Trp513Leu),were identified using whole-exome and Sanger sequencing.The AlphaFold program and Chimera software were used to analyze the effects of compound heterozygous variants on GPI structure.Results:By characterizing 53 GPI missense/nonsense variants from previous literature and two novel missense variants identified in this study,we found that most variants were located in exons 3,4,12,and 18,with a few localized in exons 8,9,and 14.This study identified novel compound heterozygous variants associated with GPI deficiency.These pathogenic variants disrupt hydrogen bonds formed by highly conserved GPI amino acids.Conclusion:Early family-based sequencing analyses,especially for patients with congenital anemia,can help increase diagnostic accuracy for GPI deficiency,improve child healthcare,and enable genetic counseling.
基金This work was supported by the Beijing Talent Fund for Young Sci-Tech Researchers (No. H013610050112)
文摘A new dinuclear centrosymmetric complex [LaL(HL)(H2O)3]2(2H2O (H2L = 3-nitrophthalic acid, NPA) was synthesized in water/ethanol solution and characterized by X-ray diffraction, IR spectrum and TGA-DTA. The complex crystallizes in triclinic system, space group P1^- with a = 8.1549(16), b = 8.8856(18), c = 15.277(3)A,α= 100.93(3),α= 90.81(3), γ= 104.56(3)°, V = 1049.8(4)A^3, Z = 1,μ= 2.125 mm^-1, Dc=1.994 g/cm^3, R = 0.0259 and wR = 0.0679. Two 3-nitrophthalates(2-) coordinate with the La3+ ions in a bridging mode, and two monohydrogen- 3-nitrophthates(1-) and three waters in terminal ways, respectively. Each La^3+ ion is nine-coordinated to exhibit a distorted tricapped trigonal prism coordination polyhedron. Both the coordinated and crystal waters are involved in the inter- and intramolecular hydrogen bonds. The dinuclear units are linked into a 2D network structure in the ab plane via intermolecular hydrogen bonds along the axes a and b. Two crystal waters fill each rhombic pore of the network. The networks are further packed along the c axis forming a layered supramolecular structure through the C-H…O weak forces between the adjacent sheets. TGA analysis shows the complex undergoes the loss of waters of crystallization and coordination and the decomposition of ligands sequentially.
基金Supported by the 973 key program of the MOST(2010CB933501,2012CB821705)the Chinese Academy of Sciences(KJCX2-YW-319,KJCX2-EW-H01)+1 种基金the National Natural Science Foundation of Chinathe Natural Science Foundation of Fujian Province(2007HZ0001-1,2009HZ0004-1,2009HZ0005-1,2009HZ0006-1,2006L2005)
文摘The solvothermal reaction of CuI with 5-amino-2-benzimidazolethiol in acetonitrile condition affords complex [Cuz(5-amino-2-benzimidazolethiol)2]2 which has been characterized by elemental analysis, infrared spectrum and single-crystal X-ray diffraction analysis. Crystal data for C28H24N12S4Cu4: monoclinic, space group C2/c with a = 15.970(5), b = 12.365(4), c = 16.293(5) A, fl = 91.977(6)°, V = 3215.5(18), Z = 4, Mr= 910.99, Dc= 1.882 g/cm3 , F(000) = 1824, p = 2.913 mm-1, λ(MoKa) = 0.71073A, T= 293(2) K, the final R = 0.0527 and wR = 0.1342. X-ray diffraction analysis revealed that the title complex exhibits a l D channel constructed from tetranuclear-copper(I) motifs connected by hydrogen bonds and shows strong photoluminescence in the solid state at room temperature.
基金Supported by the National Natural Science Foundation of China(Nos.21361023 and 21461023)
文摘A new coordination polymer, {[Cd(OPY)(tdc)(HO)]·H2 O}n(OPY = 4,4?-(oxybis(4,1-phenylene))dipyridine, H2 tdc = thiophene-2,5-dicarboxylic acid), has been synthesized hydrothermally based on a V-shaped ligand OPY. The structure was fully characterized by elemental analysis, FT-IR spectroscopy, and X-ray single-crystal diffraction analysis. In1, two OPY ligands and one water molecule acted as terminal ligands coordinating to Cdcation to form [Cd(OPY)HO]units, which are then linked by tdc2-ligands to generate a one-dimensional chain. Every two adjacent chains linked by extensive O–H···O hydrogen bonds constitute one-dimensional double-chains, and such chains are extended into two-dimensional layers via O–H···N hydrogen bonds. These layers are further connected to form a three-dimensional supramolecular architecture via π-π stacking interactions. In addition, the thermal stability and solid state fluorescence property of 1 were also investigated.
文摘A two-dimensional hydrogen-bonded cadmium(II) compound [Cd(dapm)2- (CH3COO)2(H2O)2] (dapm = diaminodiphenylmethane) has been synthesized and characterized by single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group C2/c with a = 27.572(3), b = 5.5064(5), c = 23.310(2) , = 124.785(1)o, C15H19Cdo.5ON2O3, Mr =331.52, V = 2906.6(5) ?, Z = 4, Dc = 1.515 g/cm3, F(000) = 1368 and = 0.801 mm-1. The final R = 0.0403 and wR = 0.1014 for 1795 observed reflections with I≥4(I). The centrosymmetric Cd(II) is six- coordinated in a distorted octahedral geometry, and the dapm in a trans mode acts as a monoden- tate ligand. The intermolecular hydrogen bonds among coordinated aqua molecules with coordi- nated acetate oxygen atoms and uncoordinated dapm nitrogen atoms form a two-dimensional supramolecular framework.
基金supported by the National Natural Science Foundation of China (No. 29890210) and the Key Project of the Chinese Academy of Sciences (KJCX2-H3)
文摘The assembly of 1,4-benzenedicarboxylic acid (H2bdc), 4,4?bipyridine (4,4?bipy), trimethyltin chloride and MnBr24H2O in hydrothermal conditions gave rise to a hydrogen-bonded three-dimensional complex {[Mn(4,4?bipy)4H2O](bdc)}n which has been characterized by single- crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P2/n with a = 7.0001(2), b = 11.5540(3), c = 11.4192(1) ? = 101.754(2)? V = 904.21(4) 3, Z = 2, C18H20MnN2O8, Mr = 447.30, Dc = 1.643 g/cm3, F(000) = 462 and m(MoK? = 0.783 mm-1. The final R and wR are 0.0499 and 0.1301, respectively for 1335 observed reflections with I ≥ 2(I). The Mn (Ⅱ) is six-coordinated in a distorted octahedral geometry. 4,4?Bipyridine in a m-bridge mode links [Mn(H2O)4]2+ into a linear cation chain. bdc acts as a counter anion and links the linear chains into a three-dimensional structure through hydrogen bonds.
文摘The title compound (C14H12N2O2, Mr = 240.26) crystallizes in the monoclinic system, space group P21/a with a = 7.394(1), b = 21.334(3), c = 7.423(1) ? b = 89.82(1)? V = 1170.8(3) ?, Z = 4, Dc = 1.363 g/cm3, m(MoKa) = 0.93 cm-1 and F(000) = 504.00. The final R and wR are 0.0440 and 0.1370 for 2153 observed reflections (I > 2s(I)), respectively. The dihedral angle between the two phenyl rings is 52.9 and that between the NO2 group and its attached ring is 3.0. In the crystal, molecules are stacked along [100] through p…p interactions. The CH…O hydrogen bond (3.403 ? 120.4? laterally connects the stacks along [010] to form networks (001) which are further anti- parallelly connected by CH…O (3.382 ? 142.9) and p…p interactions extending along [001]. Also presented here is a brief study on the CH…O hydrogen bonds in nitro-substituted benzyl-ideneanilines which can be classified into five types, namely, )5(12R, )4(21R, )8(22R, )6(12R and )7(22R, with the first three occurring more often.
基金supported by the Science and Technology Program of Shaanxi Province,China(No.2013K02-25)the Science and Technology Program of Xi’an,China(No.NC1404)+1 种基金the Science and Technology Research and Development Program of Shaanxi Province,China(No.14JF025)the college students innovative training program of Northwest University,China(No.2017214)
文摘1-(3-Fluorobenzoyl)-3-(4-trifluoromethylphenyl)thiourea, C15H10F4N2OS, has been synthesized firstly and determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in monoclinic system, space group C2/c with a = 31.87(3), b = 7.705(9), c = 12.591(14) A°, b = 106.06(2)°, V = 2971(6) A°^3, Z = 8, Dc=1.530 g·cm^-1, F(000) = 1392, m = 0.266 mm^–1, S = 1.06, the final R = 0.070 and w R(I 〉 2s(I)) = 0.249. The crystal structure revealed that the carbonyl thiourea unit in the determined compound was mostly planar due in part to the formation of intramolecular N–H···O=C and C–H···S=C hydrogen bonds that form two S(6) rings. The intermolecular contacts of the crystal structure have been preformed based on the Hirshfeld surface and their associated 2D fingerprint plots. In the packing diagram of the synthesized compound, the C=S group formed two types of intermolecular hydrogen bonds by the H–N(C=O) group and the H–C of the phenyl ring, respectively, and they formed R2^2(8) and R2^2(14) ring motifs, respectively. The crystal packing form was also stabilized by the intermolecular hydrogen bonds C–H···O(1–x, y, 0.5–z) with the R2^2(10) ring motifs. In addition, supramolecular layers sustained by π-π stacking interactions(between the C(2)~C(7) rings with the C(10)~C(15) rings) are formed in the crystal structure of the title compound. The electronic and reactivity were assessed by the natural bond orbital(NBO) analysis in this study.