The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isotherma...The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isothermal hydrogen and antihydrogen are injected into a palladium crystal leading to a plasma state composed of particles and antiparticles. The collapse of this state releases a huge amount of energy which can be used as fuel for space shuttles. Thus, the novel system of isothermal pressure interaction enhances the energy power carried out by the quantum ion acoustic soliton (QIAS). In addition to the energy power released from the particle-antiparticle annihilation. The probability of merging the energy from these two cases is available at certain condition. The released energy may be a significant step in solving the energy scape of Tokomak to produce fusion energy. The study starting from the one-dimensional quantum hydrodynamic model (in which the term of electron-positron and proton-antiproton for hydrogen-antihydrogen is included), a Korteweg de Vries equation (kdv) is derived, the QIAS energy experiences and the annihilation energy power are calculated. It is found that the total energy of QIAS and the energy resulting from hydrogen-antihydrogen annihilation are important step towards the establishment of a cold fusion power station.展开更多
Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics.The widely adopted strategies to enhance charge transport,such as restraining intermolecular vibratio...Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics.The widely adopted strategies to enhance charge transport,such as restraining intermolecular vibration,are mostly limited to organic molecules,which are nearly inoperative in 2D inor-ganic molecular crystals currently.In this contribution,charge transport in 2D inorganic molecular crystals is improved by integrating charge-delocalized Se8 rings as building blocks,where the delocalized electrons on Se8 rings lift the intermolecular orbitals overlap,offering efficient charge transfer channels.Besides,α-Se flakes composed of charge-delocalized Se8 rings possess small exciton binding energy.Benefitting from these,α-Se flake exhibits excellent photodetection performance with an ultrafast response rate(�5μs)and a high detectivity of 1.08�1011 Jones.These findings contribute to a deeper under-standing of the charge transport of 2D inorganic molecular crystals composed of electron-delocalized inorganic molecules and pave the way for their poten-tial application in optoelectronics.展开更多
Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)i...Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)is beneficial to elucidate the intrinsic charge-transport behavior.Next,the ultrathin conducting channel can reduce bulk injection resistance to extract mobility accurately.Then,direct exposure of the conducting channel can enhance the sensing performance.Finally,MMCs combine the merits of ultrathin thickness and high crystallization,which will improve the optoelectronic performance and realize complex device architectures for future advanced optoelectronic applications.In this Review,recent research progress in precise preparations and advanced applications of solution-processed MMCs are summarized.We present the current challenges related to MMCs with specific structures and desired performances,and an outlook regarding their application in next-generation integrated organic optoelectronics is provided.展开更多
Flexible molecular crystal waveguides based on elastic molecular crystals(EMCs)are essential inflexible and compact optical materials.An increased loss coeffi-cientαdue to self-absorption is often a problem in optical ...Flexible molecular crystal waveguides based on elastic molecular crystals(EMCs)are essential inflexible and compact optical materials.An increased loss coeffi-cientαdue to self-absorption is often a problem in optical waveguides(OWGs)offluorescent chemical materials waveguiding photons in active mode.Herein,the development of anthracene-based elastic mixed molecular crystals(EMMCs)is reported for Förster Resonance Energy Transfer(FRET)-assisted OWG.To yield a FRET crystal system based on elastic molecular crystals,1%–5%accep-tor doping forfluorescent molecular crystals of 9,10-dibromoanthracene 1 was successful by selecting the same regioisomer having electron-withdrawing group,9,10-diformylanthracene 2,as a dopant.In addition to conversion to the mixed system,there is a difference in the elastic modulus and hardness in EMC C1 and EMMC C2@1.However,the elastic behaviour was also shown in a few percent doping of the acceptor.Theαvalue of this EMMC,composed of 1 including 1%of 2(0.0077 dB/μm),is much lower than that of EMC composed of 1(0.1258 dB/μm)because of reducing self-absorption in the FRET system.An efficient andflexible OWG was successfully developed by selecting an appropriate acceptor molecule and its low doping rate for mixed crystal construction.This method is a practical approach in various functional andflexible crystal systems.展开更多
Comprehensive Summary Since the concept of 2D inorganic molecular crystals(2DIMCs)was introduced,intensive attentions have been gradually devoted to this field.Herein,the very recent advances in growth,properties,and ...Comprehensive Summary Since the concept of 2D inorganic molecular crystals(2DIMCs)was introduced,intensive attentions have been gradually devoted to this field.Herein,the very recent advances in growth,properties,and applications of 2D inorganic molecular crystals are comprehensively reviewed.Firstly,the newly emerged 2DIMCs are classified into three categories.Then the two typical production methods are present,thus leading to discrepancy in size,distribution,morphology and structures of 2DIMCs.Moreover,the unique physicochemical properties of 2DIMCs are demonstrated on the basis of the as-obtained 2DIMCs,the various applications are exhibited,demonstrating significant potential in related fields.Finally,the perspective and prospects are outlooked to offer insights in further development of 2DIMCs.展开更多
Doping is a critically important strategy to modulate the properties of organic semiconductors(OSCs) to improve their optoelectrical performances. Conventional bulk doping involves the incorporation of foreign molecul...Doping is a critically important strategy to modulate the properties of organic semiconductors(OSCs) to improve their optoelectrical performances. Conventional bulk doping involves the incorporation of foreign molecular species(i.e., dopants) into the lattice of the host OSCs, and thus disrupts the packing of the host OSCs and induces structural defects, which tends to reduce the mobility and(or) the on/off ratio in organic field-effect transistors(OFETs). In this article, we report a highly efficient and highly controllable surface doping strategy utilizing 2D molecular crystals(2DMCs) as dopants to boost the mobility and to modulate the threshold voltage of OFETs. The amount of dopants, i.e., the thickness of the 2DMCs, is controlled at monolayer precision, enabling fine tuning of the electrical properties of the OSCs at unprecedented accuracy. As a result, a prominent increase of the average mobility from 1.31 to 4.71 cm2 V-1 s-1 and a substantial reduction of the threshold voltage from -18.5 to -1.8 V are observed. Meanwhile, high on/off ratios of up to 108 are retained.展开更多
Artificial synaptic devices hold great potential in building neuromorphic computers.Due to the unique morphological features,twodimensional organic semiconductors at the monolayer limit show interesting properties whe...Artificial synaptic devices hold great potential in building neuromorphic computers.Due to the unique morphological features,twodimensional organic semiconductors at the monolayer limit show interesting properties when acting as the active layers for organic field-effect transistors.Here,organic synaptic transistors are prepared with 1,4-bis((5’-hexyl-2,2’-bithiophen-5-yl)ethyl)benzene(HTEB)monolayer molecular crystals.Functions similar to biological synapses,including excitatory postsynaptic current(EPSC),pair-pulse facilitation,and short/long-term memory,have been realized.The synaptic device achieves the minimum power consumption of 4.29 fJ at low drain voltage of−0.01 V.Moreover,the HTEB synaptic device exhibits excellent long-term memory with 109 s EPSC estimated retention time.Brain-like functions such as dynamic learning-forgetting process and visual noise reduction are demonstrated by nine devices.The unique morphological features of the monolayer molecular semiconductors help to reveal the device working mechanism,and the synaptic behaviors of the devices can be attributed to oxygen induced energy level.This work shows the potential of artificial neuroelectronic devices based on organic monolayer molecular crystals.展开更多
Arrays of low-dimensional molecular crystals of square columns(1-D)and nanolamellae(2-D)of Zn[TCNQ]_(2)(H_(2)O)_(2)with large areas(up to 1020 cm^(2))have been synthesized by controlled addition of water to Zn and TCN...Arrays of low-dimensional molecular crystals of square columns(1-D)and nanolamellae(2-D)of Zn[TCNQ]_(2)(H_(2)O)_(2)with large areas(up to 1020 cm^(2))have been synthesized by controlled addition of water to Zn and TCNQ.Based on the ability to accurately control the reaction,a new moisture and water indicator has been developed.The simple method,the large areas of material prepared,the fine size tuning,and the typical semiconductor behavior of the resulting low-dimensional molecular materials promise applications in molecular electronics as well as nanoelectronics.The system is an effective indicator for the detection of traces of water and moisture.展开更多
The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are...The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are: (ⅰ) The dominant contributions to the electrical conductivities for crystals Ⅰ and Ⅱ are from TCNQ molecular columns, and the charge carriers are electrons. (ⅱ) The electrical conduction is mainly due to the hopping of charge carriers between the seats of lattice. (ⅲ) The considerable difference of the electrical conductivities between crystals Ⅰ and Ⅱ is due to the differences between (a) the concentrations of charge carriers n_(AⅠ)~C= 0.9988-|e|/cell and n_(AⅡ)~C=0.0340-|e|/cell; (b) the widths of the energy bands △E_(AⅠ)^(LU)=0.88 eV and △E_(AⅡ)~LU=0.040 eV; (c) the first derivative of E with respect to k, (dE/dk)_(K_FAⅠ)^(LU)=0.27 eV· and (dE/dk)_(K_FAⅡ)~LU=0.0048 eV·; and (d) the difference of energy barriers for the hopping of charge carriers ∈_Ⅱ-∈Ⅰ=2.5-8.8 kJ/mol.展开更多
Apparent polarization energy of the localized charge in organic solids consists of electronic polarization energy, permanent electrostatic interactions, and inter/intra molecular relaxation energies. The effective ele...Apparent polarization energy of the localized charge in organic solids consists of electronic polarization energy, permanent electrostatic interactions, and inter/intra molecular relaxation energies. The effective electronic polarization energies for an electron/hole carrier were successfully estimated by AMOEBA polarizable force field in naphthalene molecular crystals. Both electronic polarization energy and permanent electrostatic interaction were in agreement with the preview experimental values. In addition, the influence of the multipoles from different distributed mutipole analysis (DMA) fitting options on the electro- static interactions are discussed in this paper. We found that the multipoles obtained from Gauss-Hermite quadrature without diffuse function or grid-based quadrature with 0.325 A H atomic radius will give reasonable electronic polarization energies and permanent interactions for electron and hole carriers.展开更多
SINCE the discovery and subsequent macroscopic synthesis of fullerenes,due to their unusualstructure and widely potential applications,many theoretical and experimental scientists havedone a lot of work on fullerenes....SINCE the discovery and subsequent macroscopic synthesis of fullerenes,due to their unusualstructure and widely potential applications,many theoretical and experimental scientists havedone a lot of work on fullerenes.Fullerenes are the hollow cage molecules,the large,closedspheroidal shapes suggest that they could hold a variety of small guest atoms and/or展开更多
A SAPO-11 silicoaluminophosphate molecular sieve with stable crystal structure was synthesized for the first time. After removing template by calcination, its crystal space group still retains Icm2 which the as-synthe...A SAPO-11 silicoaluminophosphate molecular sieve with stable crystal structure was synthesized for the first time. After removing template by calcination, its crystal space group still retains Icm2 which the as-synthesized has. The catalyst deriving from the present SAPO-11 materials shows higher isomerization selectivity and higher paraffin hydroisomerization yield than those reported elsewhere.展开更多
The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102...The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102.448(3)°, V= 1992.9 (5)A63, Z = 4, Dc = 1.335 g/cm63,μ = 0.087 mm^-1 and F(000) = 848. It remains monomeric in the crystal and a tape-like structure is formed in the crystal structure of molecular clip. The most unusual structural feature of 2 is the boat conformation of its cyclohexyl ring imposed by the ring fusion at C(9)-C(9a).展开更多
4 mechanical model of liquid crystals ( LCs ) was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, an...4 mechanical model of liquid crystals ( LCs ) was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, and some dynamie parameters in a semi-experiment molecular orbit method. A novel explanation on the multi-phase formation of LC system is obtained. It is found that the value of the critical rotational velueity is a key parameter for the characterization of each homologous series. The dipole moment of the molecules was also discussed.展开更多
The effect of sintering dispersed dispersion and nano-emulsion particles of high molecular weightpolytetrafluoroethylene(PTFE)on a substrate as a function of“melt”time and temperature is described.Folded chain singl...The effect of sintering dispersed dispersion and nano-emulsion particles of high molecular weightpolytetrafluoroethylene(PTFE)on a substrate as a function of“melt”time and temperature is described.Folded chain singlecrystals parallel to the substrate and as ribbons on-edge(with double striations),as well as bands,are produced for longersintering times;particle merger and diffusion of individual molecules,crystallizing as folded chain,single(or few)molecule,single crystals when“trapped”on the substrate by cooling occur for shorter sintering times.It is suggested the observedstructures develop with sintering time,in a mesomorphic melt.The structure of the nascent particles is also discussed.展开更多
Twin gold crystal nanowires, whose loading direction is parallel to the twin boundary orientation, are simulated.We calculate the nanowires under tensile or compressive loads, different length nanowires, and different...Twin gold crystal nanowires, whose loading direction is parallel to the twin boundary orientation, are simulated.We calculate the nanowires under tensile or compressive loads, different length nanowires, and different twin boundary nanowires respectively. The Young modulus of nanowires under compressive load is about twice that under tensile load.The compressive properties of twin gold nanowires are superior to their tensile properties. For different length nanowires,there is a critical value of length with respect to the mechanical properties. When the length of nanowire is greater than the critical value, its mechanical properties are sensitive to length. The twin boundary spacing hardly affects the mechanical properties.展开更多
The title compound 4-(2-acetonyl-selanyl-benzamido) benzoic acid was synthesized and its structure was determined by NMR, HR MS and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/...The title compound 4-(2-acetonyl-selanyl-benzamido) benzoic acid was synthesized and its structure was determined by NMR, HR MS and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 5.18537(19), b = 18.9308(7), c = 16.6586(5) ?, b = 95.857(3)°, V = 1626.72(10) ?3, Z = 4, Dc = 1.536 g/cm3, m = 3.302 mm-1, F(000) = 760, the final R = 0.0466 and wR = 0.1353 for 2308 observed reflections with I > 2σ(I). In silico docking studies were carried out to evaluate the anti-ischemic stroke activities for twenty-one ischemic stroke associated proteins by Autodock 4.2 software. The title compound has better activity against ischemic stroke than Ebselen.展开更多
1 Introduction C<sub>60</sub> crystal is a new form of pure, solid carbon and has been widely investigated. But until now, there still exists the ambiguity in its crystal structure. Early paper showed that...1 Introduction C<sub>60</sub> crystal is a new form of pure, solid carbon and has been widely investigated. But until now, there still exists the ambiguity in its crystal structure. Early paper showed that C<sub>60</sub> molecules stack in a hexagonal close-packed (hcp) lattice with α=10.02A, c=16.36A, but other ones reported that C<sub>60</sub> crystal has a face-centred-cubic (foe) lattice with α=14.172,. Foc and hcp structures are both stable at room temperature, whereas from the energetic point of view, fcc structure is much stabler. Moreover, the differences in the展开更多
The crystal structure of the title compound ((C 6H 5CONC 6H 4S) 2, M r =229) has been determined by X ray diffraction analysis. The crystal belongs to triclinic space group P 1 with cell parameters: a=...The crystal structure of the title compound ((C 6H 5CONC 6H 4S) 2, M r =229) has been determined by X ray diffraction analysis. The crystal belongs to triclinic space group P 1 with cell parameters: a=7.957(4), b=11.570(7), c=12 335(6), α=76.68(4), β=81.48(4), γ=87.26(4)°, V=1092.9 3, Z=2, D c =1 39g/cm 3, F(000)=476, μ (Mo Kα )=2.7mm -1 . The final R factor is 0.0373 for 3764 observed reflections. The result of X ray diffraction analysis indicates that all of these single bond lengths are obviously shorter than that of standard single bond. Those atoms might take part in a conjugate system. The electrons for sp 3 hybridized S(1) and S(2) move toward two sides and the densities of electronic cloud among them are reduced and can be easily broken. The obtained results can explain the reaction mechanism of the title compound.展开更多
Chemical vapor deposition has been widely used to prepare the films of silicon, diamond and other inorganic species. Preparation of molecular crystal from chemical reactions in the vapor phase is seldom reported. Hept...Chemical vapor deposition has been widely used to prepare the films of silicon, diamond and other inorganic species. Preparation of molecular crystal from chemical reactions in the vapor phase is seldom reported. Hepta-condensed form of 1-propyne-1. 3-diol molecular crystal produced via vapor phase chemical reaction is reported and展开更多
文摘The main purpose of this work is to shed light on the possibility of producing huge amount of energy based on the construction matter-antimatter plasma in a molecular crystal. It is assumed that two beams of isothermal hydrogen and antihydrogen are injected into a palladium crystal leading to a plasma state composed of particles and antiparticles. The collapse of this state releases a huge amount of energy which can be used as fuel for space shuttles. Thus, the novel system of isothermal pressure interaction enhances the energy power carried out by the quantum ion acoustic soliton (QIAS). In addition to the energy power released from the particle-antiparticle annihilation. The probability of merging the energy from these two cases is available at certain condition. The released energy may be a significant step in solving the energy scape of Tokomak to produce fusion energy. The study starting from the one-dimensional quantum hydrodynamic model (in which the term of electron-positron and proton-antiproton for hydrogen-antihydrogen is included), a Korteweg de Vries equation (kdv) is derived, the QIAS energy experiences and the annihilation energy power are calculated. It is found that the total energy of QIAS and the energy resulting from hydrogen-antihydrogen annihilation are important step towards the establishment of a cold fusion power station.
基金supported by the National Natural Science Foundation of China(Grant Nos.U21A2069,21825103)the China Postdoctoral Science Foundation(Grant No.2021M691108).
文摘Outstanding charge transport in molecular crystals is of great importance in modern electronics and optoelectronics.The widely adopted strategies to enhance charge transport,such as restraining intermolecular vibration,are mostly limited to organic molecules,which are nearly inoperative in 2D inor-ganic molecular crystals currently.In this contribution,charge transport in 2D inorganic molecular crystals is improved by integrating charge-delocalized Se8 rings as building blocks,where the delocalized electrons on Se8 rings lift the intermolecular orbitals overlap,offering efficient charge transfer channels.Besides,α-Se flakes composed of charge-delocalized Se8 rings possess small exciton binding energy.Benefitting from these,α-Se flake exhibits excellent photodetection performance with an ultrafast response rate(�5μs)and a high detectivity of 1.08�1011 Jones.These findings contribute to a deeper under-standing of the charge transport of 2D inorganic molecular crystals composed of electron-delocalized inorganic molecules and pave the way for their poten-tial application in optoelectronics.
基金supported by the National Key R&D Plan of China(2022YFB3603800 and 2020YFB0204802)the National Natural Science Foundation of China(T2225028 and 22075295)+2 种基金Chinese Academy of Sciences(Hundred Talents PlanYouth Innovation Promotion Association,Young Scientists in Basic Research(YSBR-053))the Strategic Priority Research Program of Science(XDB0520201).
文摘Emerging monolayer molecular crystals(MMCs)have become prosperous in recent decades due to their numerous advantages.First,downsizing the active layer thickness to monolayer in organic field-effect transistors(OFETs)is beneficial to elucidate the intrinsic charge-transport behavior.Next,the ultrathin conducting channel can reduce bulk injection resistance to extract mobility accurately.Then,direct exposure of the conducting channel can enhance the sensing performance.Finally,MMCs combine the merits of ultrathin thickness and high crystallization,which will improve the optoelectronic performance and realize complex device architectures for future advanced optoelectronic applications.In this Review,recent research progress in precise preparations and advanced applications of solution-processed MMCs are summarized.We present the current challenges related to MMCs with specific structures and desired performances,and an outlook regarding their application in next-generation integrated organic optoelectronics is provided.
基金Funding information JST FOREST Program,Grant/Award Number:JPMJFR211WKAKENHI+2 种基金Aid for Scicntific Rescarch on Innovative Areas‘π-figuration'Grant/Award Number:17H05171Japan Socicty for the Promotion of Science(JSPS)Early-Career Scientists,Grant/Award Number:22K14671。
文摘Flexible molecular crystal waveguides based on elastic molecular crystals(EMCs)are essential inflexible and compact optical materials.An increased loss coeffi-cientαdue to self-absorption is often a problem in optical waveguides(OWGs)offluorescent chemical materials waveguiding photons in active mode.Herein,the development of anthracene-based elastic mixed molecular crystals(EMMCs)is reported for Förster Resonance Energy Transfer(FRET)-assisted OWG.To yield a FRET crystal system based on elastic molecular crystals,1%–5%accep-tor doping forfluorescent molecular crystals of 9,10-dibromoanthracene 1 was successful by selecting the same regioisomer having electron-withdrawing group,9,10-diformylanthracene 2,as a dopant.In addition to conversion to the mixed system,there is a difference in the elastic modulus and hardness in EMC C1 and EMMC C2@1.However,the elastic behaviour was also shown in a few percent doping of the acceptor.Theαvalue of this EMMC,composed of 1 including 1%of 2(0.0077 dB/μm),is much lower than that of EMC composed of 1(0.1258 dB/μm)because of reducing self-absorption in the FRET system.An efficient andflexible OWG was successfully developed by selecting an appropriate acceptor molecule and its low doping rate for mixed crystal construction.This method is a practical approach in various functional andflexible crystal systems.
基金the National Key R&D Program of China(2021YFA0717900)the National Natural Science Foundation of China(Grant 52002267)the Natural Science Foundation of Tianjin City(22JCJQJC00080,20JCQNJC01990).
文摘Comprehensive Summary Since the concept of 2D inorganic molecular crystals(2DIMCs)was introduced,intensive attentions have been gradually devoted to this field.Herein,the very recent advances in growth,properties,and applications of 2D inorganic molecular crystals are comprehensively reviewed.Firstly,the newly emerged 2DIMCs are classified into three categories.Then the two typical production methods are present,thus leading to discrepancy in size,distribution,morphology and structures of 2DIMCs.Moreover,the unique physicochemical properties of 2DIMCs are demonstrated on the basis of the as-obtained 2DIMCs,the various applications are exhibited,demonstrating significant potential in related fields.Finally,the perspective and prospects are outlooked to offer insights in further development of 2DIMCs.
基金supported by the National Natural Science Foundation of China (51873148, 61674116, 51633006)the Ministry of Science and Technology of China (2016YFA0202302)the Natural Science Foundation of Tianjin City (18JC-YBJC18400)。
文摘Doping is a critically important strategy to modulate the properties of organic semiconductors(OSCs) to improve their optoelectrical performances. Conventional bulk doping involves the incorporation of foreign molecular species(i.e., dopants) into the lattice of the host OSCs, and thus disrupts the packing of the host OSCs and induces structural defects, which tends to reduce the mobility and(or) the on/off ratio in organic field-effect transistors(OFETs). In this article, we report a highly efficient and highly controllable surface doping strategy utilizing 2D molecular crystals(2DMCs) as dopants to boost the mobility and to modulate the threshold voltage of OFETs. The amount of dopants, i.e., the thickness of the 2DMCs, is controlled at monolayer precision, enabling fine tuning of the electrical properties of the OSCs at unprecedented accuracy. As a result, a prominent increase of the average mobility from 1.31 to 4.71 cm2 V-1 s-1 and a substantial reduction of the threshold voltage from -18.5 to -1.8 V are observed. Meanwhile, high on/off ratios of up to 108 are retained.
基金the National Natural Science Foundation of China(No.62074111)the Science and Technology Foundation of Shanghai(Nos.19JC1412402 and 20JC1415600)+3 种基金Shanghai Municipal Science and Technology Major Project(No.2021SHZDZX0100)Shanghai Municipal Commission of Science and Technology Project(No.19511132101)the Chinese Academy of Sciences(Hundred Talents Plan),the China Postdoctoral Science Foundation funded project(No.2019M660807)the support of the Fundamental Research Funds for the Central Universities.
文摘Artificial synaptic devices hold great potential in building neuromorphic computers.Due to the unique morphological features,twodimensional organic semiconductors at the monolayer limit show interesting properties when acting as the active layers for organic field-effect transistors.Here,organic synaptic transistors are prepared with 1,4-bis((5’-hexyl-2,2’-bithiophen-5-yl)ethyl)benzene(HTEB)monolayer molecular crystals.Functions similar to biological synapses,including excitatory postsynaptic current(EPSC),pair-pulse facilitation,and short/long-term memory,have been realized.The synaptic device achieves the minimum power consumption of 4.29 fJ at low drain voltage of−0.01 V.Moreover,the HTEB synaptic device exhibits excellent long-term memory with 109 s EPSC estimated retention time.Brain-like functions such as dynamic learning-forgetting process and visual noise reduction are demonstrated by nine devices.The unique morphological features of the monolayer molecular semiconductors help to reveal the device working mechanism,and the synaptic behaviors of the devices can be attributed to oxygen induced energy level.This work shows the potential of artificial neuroelectronic devices based on organic monolayer molecular crystals.
基金The authors acknowledge the financial support from the National Natural Science Foundation of China(Nos.20721061,50725311)the Ministry of Science and Technology of China(2006CB806200,2006CB932100)and the Chinese Academy of Sciences.
文摘Arrays of low-dimensional molecular crystals of square columns(1-D)and nanolamellae(2-D)of Zn[TCNQ]_(2)(H_(2)O)_(2)with large areas(up to 1020 cm^(2))have been synthesized by controlled addition of water to Zn and TCNQ.Based on the ability to accurately control the reaction,a new moisture and water indicator has been developed.The simple method,the large areas of material prepared,the fine size tuning,and the typical semiconductor behavior of the resulting low-dimensional molecular materials promise applications in molecular electronics as well as nanoelectronics.The system is an effective indicator for the detection of traces of water and moisture.
基金Project supported by the National Natural Science Foundation of China.
文摘The structure of electronic energy bands, electric charge distribution and the amount of charge transfer of molecular crystals 1-MCI·(TCNQ)_2 (Ⅰ) and 2-MCI· (TCNQ)_2 (Ⅱ) have been studied. The results are: (ⅰ) The dominant contributions to the electrical conductivities for crystals Ⅰ and Ⅱ are from TCNQ molecular columns, and the charge carriers are electrons. (ⅱ) The electrical conduction is mainly due to the hopping of charge carriers between the seats of lattice. (ⅲ) The considerable difference of the electrical conductivities between crystals Ⅰ and Ⅱ is due to the differences between (a) the concentrations of charge carriers n_(AⅠ)~C= 0.9988-|e|/cell and n_(AⅡ)~C=0.0340-|e|/cell; (b) the widths of the energy bands △E_(AⅠ)^(LU)=0.88 eV and △E_(AⅡ)~LU=0.040 eV; (c) the first derivative of E with respect to k, (dE/dk)_(K_FAⅠ)^(LU)=0.27 eV· and (dE/dk)_(K_FAⅡ)~LU=0.0048 eV·; and (d) the difference of energy barriers for the hopping of charge carriers ∈_Ⅱ-∈Ⅰ=2.5-8.8 kJ/mol.
基金supported by the National Natural Science Foundation of China(21173138,21173139)the Fundamental Research Funds for the Central Universities(GK201303004)
文摘Apparent polarization energy of the localized charge in organic solids consists of electronic polarization energy, permanent electrostatic interactions, and inter/intra molecular relaxation energies. The effective electronic polarization energies for an electron/hole carrier were successfully estimated by AMOEBA polarizable force field in naphthalene molecular crystals. Both electronic polarization energy and permanent electrostatic interaction were in agreement with the preview experimental values. In addition, the influence of the multipoles from different distributed mutipole analysis (DMA) fitting options on the electro- static interactions are discussed in this paper. We found that the multipoles obtained from Gauss-Hermite quadrature without diffuse function or grid-based quadrature with 0.325 A H atomic radius will give reasonable electronic polarization energies and permanent interactions for electron and hole carriers.
基金This work was supported by the National Natural Science Foundation of China (29473103) the Natural Sciences Foundation of Shandong Province (94B0715)
文摘SINCE the discovery and subsequent macroscopic synthesis of fullerenes,due to their unusualstructure and widely potential applications,many theoretical and experimental scientists havedone a lot of work on fullerenes.Fullerenes are the hollow cage molecules,the large,closedspheroidal shapes suggest that they could hold a variety of small guest atoms and/or
文摘A SAPO-11 silicoaluminophosphate molecular sieve with stable crystal structure was synthesized for the first time. After removing template by calcination, its crystal space group still retains Icm2 which the as-synthesized has. The catalyst deriving from the present SAPO-11 materials shows higher isomerization selectivity and higher paraffin hydroisomerization yield than those reported elsewhere.
基金the National Natural Science Foundation of China (20672042)
文摘The synthesis and X-ray crystal structure of a new molecular clip 2 was reported. It (C24H24N4O2, Mr = 400.47) crystallizes in the space group C2/c with a = 15.587(2), b = 8.5805(12), c = 15.259(2) A, β = 102.448(3)°, V= 1992.9 (5)A63, Z = 4, Dc = 1.335 g/cm63,μ = 0.087 mm^-1 and F(000) = 848. It remains monomeric in the crystal and a tape-like structure is formed in the crystal structure of molecular clip. The most unusual structural feature of 2 is the boat conformation of its cyclohexyl ring imposed by the ring fusion at C(9)-C(9a).
文摘4 mechanical model of liquid crystals ( LCs ) was used to explain the phase formation and thermal properties . The LC plusses in the model are micro- machine systems consisting of an ensemble of molecular rotors, and some dynamie parameters in a semi-experiment molecular orbit method. A novel explanation on the multi-phase formation of LC system is obtained. It is found that the value of the critical rotational velueity is a key parameter for the characterization of each homologous series. The dipole moment of the molecules was also discussed.
文摘The effect of sintering dispersed dispersion and nano-emulsion particles of high molecular weightpolytetrafluoroethylene(PTFE)on a substrate as a function of“melt”time and temperature is described.Folded chain singlecrystals parallel to the substrate and as ribbons on-edge(with double striations),as well as bands,are produced for longersintering times;particle merger and diffusion of individual molecules,crystallizing as folded chain,single(or few)molecule,single crystals when“trapped”on the substrate by cooling occur for shorter sintering times.It is suggested the observedstructures develop with sintering time,in a mesomorphic melt.The structure of the nascent particles is also discussed.
基金supported by the National Science and Technology Pillar Program,China(Grant No.2015BAK17B06)the Earthquake Industry Special Science Research Foundation Project,China(Grant No.201508026-02)+1 种基金the Natural Science Foundation of Heilongjiang Province,China(Grant No.A201310)the Scientific Research Starting Foundation for Post Doctorate of Heilongjiang Province,China(Grant No.LBHQ13040)
文摘Twin gold crystal nanowires, whose loading direction is parallel to the twin boundary orientation, are simulated.We calculate the nanowires under tensile or compressive loads, different length nanowires, and different twin boundary nanowires respectively. The Young modulus of nanowires under compressive load is about twice that under tensile load.The compressive properties of twin gold nanowires are superior to their tensile properties. For different length nanowires,there is a critical value of length with respect to the mechanical properties. When the length of nanowire is greater than the critical value, its mechanical properties are sensitive to length. The twin boundary spacing hardly affects the mechanical properties.
基金supported by the Natural Science Foundation of Henan Province(No.182300410353)the Doctoral Research Start-up Fund of Henan University of Science and Technology(No.4008/13480055)
文摘The title compound 4-(2-acetonyl-selanyl-benzamido) benzoic acid was synthesized and its structure was determined by NMR, HR MS and X-ray single-crystal diffraction. The crystal belongs to monoclinic, space group P21/n, with a = 5.18537(19), b = 18.9308(7), c = 16.6586(5) ?, b = 95.857(3)°, V = 1626.72(10) ?3, Z = 4, Dc = 1.536 g/cm3, m = 3.302 mm-1, F(000) = 760, the final R = 0.0466 and wR = 0.1353 for 2308 observed reflections with I > 2σ(I). In silico docking studies were carried out to evaluate the anti-ischemic stroke activities for twenty-one ischemic stroke associated proteins by Autodock 4.2 software. The title compound has better activity against ischemic stroke than Ebselen.
文摘1 Introduction C<sub>60</sub> crystal is a new form of pure, solid carbon and has been widely investigated. But until now, there still exists the ambiguity in its crystal structure. Early paper showed that C<sub>60</sub> molecules stack in a hexagonal close-packed (hcp) lattice with α=10.02A, c=16.36A, but other ones reported that C<sub>60</sub> crystal has a face-centred-cubic (foe) lattice with α=14.172,. Foc and hcp structures are both stable at room temperature, whereas from the energetic point of view, fcc structure is much stabler. Moreover, the differences in the
文摘The crystal structure of the title compound ((C 6H 5CONC 6H 4S) 2, M r =229) has been determined by X ray diffraction analysis. The crystal belongs to triclinic space group P 1 with cell parameters: a=7.957(4), b=11.570(7), c=12 335(6), α=76.68(4), β=81.48(4), γ=87.26(4)°, V=1092.9 3, Z=2, D c =1 39g/cm 3, F(000)=476, μ (Mo Kα )=2.7mm -1 . The final R factor is 0.0373 for 3764 observed reflections. The result of X ray diffraction analysis indicates that all of these single bond lengths are obviously shorter than that of standard single bond. Those atoms might take part in a conjugate system. The electrons for sp 3 hybridized S(1) and S(2) move toward two sides and the densities of electronic cloud among them are reduced and can be easily broken. The obtained results can explain the reaction mechanism of the title compound.
文摘Chemical vapor deposition has been widely used to prepare the films of silicon, diamond and other inorganic species. Preparation of molecular crystal from chemical reactions in the vapor phase is seldom reported. Hepta-condensed form of 1-propyne-1. 3-diol molecular crystal produced via vapor phase chemical reaction is reported and