The mechanism of contact electrification between metals was studied using the first-principles method, taking the Ag-Fe contact as an example. Charge population, charge density difference, the orbitals and densities o...The mechanism of contact electrification between metals was studied using the first-principles method, taking the Ag-Fe contact as an example. Charge population, charge density difference, the orbitals and densities of states （DOS） were calculated to study the electronic properties of the contacting interfacial atoms. Based on the calculation, the amount of contact charge was obtained. The investigation revealed that the electrons near Fermi levels with higher energies transfer between the outermost orbitals （s orbitals for Ag and d orbitals for Fe）. Meanwhile, polarized covalent bonds form between the d electrons in the deep energy states. These two effects together lead to an increase of charge magnitude at the interface. Also, the electrons responsible for electrification can be determined by their energies and orbitals.展开更多
The title complex cis-bis（tetrahydrothiophene）-bis（nitrate） platinum（H）, （tht）2Pt（NO3）2, was the reducing product from potassium hexachloroplatinate（IV） K2PtC16 where the platinum is tetra-valenced. Crysta...The title complex cis-bis（tetrahydrothiophene）-bis（nitrate） platinum（H）, （tht）2Pt（NO3）2, was the reducing product from potassium hexachloroplatinate（IV） K2PtC16 where the platinum is tetra-valenced. Crystal data for CsH16N206PtS2： monoclinic, space group P21/c, a = 9.8833（5）, b = 8.6744（4）, c = 18.6407（9）A,β = 114.401（3）°, V = 1455.35（12）A3 Z = 4, Mr = 495.44, Dc = 2.261 g/cm3, F（000） = 944,μ = 9.950 mm-1, 2（MoKa） = 0.71073 A, T= 293（2） K, 2θmax = 54.96°, GOOF = 1.033, R = 0.0350 and wR = 0.0785 for 2572 observed reflections with I 〉 2σ（I）. X-ray diffraction studies reveal that the title complex has interesting weak metal-metal interactions and two molecules linked by metal-metal interaction exist as a group. Luminescent spectrum illuminates red emission of the complex at room temperature.展开更多
Molecular structure of a naphthyridine and pyrazine amine ligand, N2,N7-di（pyrazin-2-yl）-1,8-naphthyri-dine-2,7-diamine（H2dpznda 1） was studied, and a three-dimensional supramolecular network with a double helix c...Molecular structure of a naphthyridine and pyrazine amine ligand, N2,N7-di（pyrazin-2-yl）-1,8-naphthyri-dine-2,7-diamine（H2dpznda 1） was studied, and a three-dimensional supramolecular network with a double helix chain structure through intermolecular hydrogen bonds and π-π interactions between the naphthyridine and pyrazine rings was depicted. Through ligand 1, [Co2（μ2-dpznda）2（μ2-CH3OH）2]（2） was obtained and two ligands coordinate to two Co2＋）as tetradentate bridging ligands. Single crystal and magnetism study on 2 revealed that the complex exhibited weak yet significant metal-metal interaction.展开更多
Comprehensive Summary The experimental investigation of rare-earth metal-metal bonds remains a challenge in the study of chemical bonds.Herein,we report the synthesis and characterization of a novel heteronuclear di-m...Comprehensive Summary The experimental investigation of rare-earth metal-metal bonds remains a challenge in the study of chemical bonds.Herein,we report the synthesis and characterization of a novel heteronuclear di-metallofullerene,ScY@C_(3v)(8)-C_(82),which contains a mixed rare-earth metal-metal bond.ScY@C_(3v)(8)-C_(82)was successfully synthesized by arc-discharging method and characterized by mass spectrometry,UV-vis-NIR spectroscopy and single-crystal X-ray diffraction crystallography,which unambiguously determined its molecular structure.Theoretical calculations were also performed to study the optimized positions of Sc-Y metallic dimer and the electronic configuration.The combined experimental and theoretical results confirmed that both Sc and Y atoms transfer two electrons to the C_(3v)(8)-C_(82)cage,i.e.,(ScY)4+@(C_(3v)(8)-C_(82))4-.In particular,a covalent Sc-Yσ2 bond,which has never been reported before,is proven to be formed inside C_(3v)(8)-C_(82)fullerene cage.This work presents a novel di-metallofullerene containing mixed rare-earth metal-metal bond and expands the understanding of metal-metal bonding of rare earth elements.展开更多
Many experimental results have shown that the property of amorphous alloys has certain relation with composition, because the change in composition can result in change in structure of amorphous alloys.So in order to ...Many experimental results have shown that the property of amorphous alloys has certain relation with composition, because the change in composition can result in change in structure of amorphous alloys.So in order to understand the influence展开更多
The platinum(II) terpyridyl acetylide complex [Pt(terpy)(C≡CR)]ClO4 (terpy=2,2'∶6'2''-terpyridine, R=CH2CH2CH3) (1) was incorporated into Nafion membranes. At high loading the dry membranes exhibit i...The platinum(II) terpyridyl acetylide complex [Pt(terpy)(C≡CR)]ClO4 (terpy=2,2'∶6'2''-terpyridine, R=CH2CH2CH3) (1) was incorporated into Nafion membranes. At high loading the dry membranes exhibit intense photoluminescence with max at 707 nm from the 3MMLCT state, which was not observed in fluid solution. Upon exposure to the vapor of polar volatile organic compounds (VOC), this photoluminescence was significantly red-shifed. This process was fully reversible when the VOC-incorporated membrane was dried in air. The dramatic and reversible changes in the emission spectra made the Nafion-supported complex as an interesting sensor candi-date for polar VOC.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 50823003 and 90923018)
文摘The mechanism of contact electrification between metals was studied using the first-principles method, taking the Ag-Fe contact as an example. Charge population, charge density difference, the orbitals and densities of states （DOS） were calculated to study the electronic properties of the contacting interfacial atoms. Based on the calculation, the amount of contact charge was obtained. The investigation revealed that the electrons near Fermi levels with higher energies transfer between the outermost orbitals （s orbitals for Ag and d orbitals for Fe）. Meanwhile, polarized covalent bonds form between the d electrons in the deep energy states. These two effects together lead to an increase of charge magnitude at the interface. Also, the electrons responsible for electrification can be determined by their energies and orbitals.
基金supported by 973 Program (2006CB932900)National Natural Science Foundation of China (No. 20571074)Natural Science Foundation of Fujian Province (No. 2007J0172)
文摘The title complex cis-bis（tetrahydrothiophene）-bis（nitrate） platinum（H）, （tht）2Pt（NO3）2, was the reducing product from potassium hexachloroplatinate（IV） K2PtC16 where the platinum is tetra-valenced. Crystal data for CsH16N206PtS2： monoclinic, space group P21/c, a = 9.8833（5）, b = 8.6744（4）, c = 18.6407（9）A,β = 114.401（3）°, V = 1455.35（12）A3 Z = 4, Mr = 495.44, Dc = 2.261 g/cm3, F（000） = 944,μ = 9.950 mm-1, 2（MoKa） = 0.71073 A, T= 293（2） K, 2θmax = 54.96°, GOOF = 1.033, R = 0.0350 and wR = 0.0785 for 2572 observed reflections with I 〉 2σ（I）. X-ray diffraction studies reveal that the title complex has interesting weak metal-metal interactions and two molecules linked by metal-metal interaction exist as a group. Luminescent spectrum illuminates red emission of the complex at room temperature.
基金supported by the Natural Science Foundation of Shaanxi Province(No.2013JM2005)the National Science Council of China and the Full-Time Master Innovation Fund of Xi’an Shiyou University(No.2015cx140735)
文摘Molecular structure of a naphthyridine and pyrazine amine ligand, N2,N7-di（pyrazin-2-yl）-1,8-naphthyri-dine-2,7-diamine（H2dpznda 1） was studied, and a three-dimensional supramolecular network with a double helix chain structure through intermolecular hydrogen bonds and π-π interactions between the naphthyridine and pyrazine rings was depicted. Through ligand 1, [Co2（μ2-dpznda）2（μ2-CH3OH）2]（2） was obtained and two ligands coordinate to two Co2＋）as tetradentate bridging ligands. Single crystal and magnetism study on 2 revealed that the complex exhibited weak yet significant metal-metal interaction.
基金the National Science Foundation China(NSFC No.52172051)the NSF of Jiangsu Province(BK20200041)+2 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)A.R.-F.and J.M.P.thank the Spanish Ministry of Science(grant PID2020-112762GB-I00 funded by MCIN/AEl/10.13039/501100011033)the Generalitat de Catalunya(grant 2021 SGR 00110)and the URV for support.
文摘Comprehensive Summary The experimental investigation of rare-earth metal-metal bonds remains a challenge in the study of chemical bonds.Herein,we report the synthesis and characterization of a novel heteronuclear di-metallofullerene,ScY@C_(3v)(8)-C_(82),which contains a mixed rare-earth metal-metal bond.ScY@C_(3v)(8)-C_(82)was successfully synthesized by arc-discharging method and characterized by mass spectrometry,UV-vis-NIR spectroscopy and single-crystal X-ray diffraction crystallography,which unambiguously determined its molecular structure.Theoretical calculations were also performed to study the optimized positions of Sc-Y metallic dimer and the electronic configuration.The combined experimental and theoretical results confirmed that both Sc and Y atoms transfer two electrons to the C_(3v)(8)-C_(82)cage,i.e.,(ScY)4+@(C_(3v)(8)-C_(82))4-.In particular,a covalent Sc-Yσ2 bond,which has never been reported before,is proven to be formed inside C_(3v)(8)-C_(82)fullerene cage.This work presents a novel di-metallofullerene containing mixed rare-earth metal-metal bond and expands the understanding of metal-metal bonding of rare earth elements.
文摘Many experimental results have shown that the property of amorphous alloys has certain relation with composition, because the change in composition can result in change in structure of amorphous alloys.So in order to understand the influence
基金Project supported by the Ministry of Science and Technology of China (Nos. G2000078104 G2000077502) and the National Natural Science Foun-dation of China and Bureau for the Basic Research of Chinese Academy of Sciences.
文摘The platinum(II) terpyridyl acetylide complex [Pt(terpy)(C≡CR)]ClO4 (terpy=2,2'∶6'2''-terpyridine, R=CH2CH2CH3) (1) was incorporated into Nafion membranes. At high loading the dry membranes exhibit intense photoluminescence with max at 707 nm from the 3MMLCT state, which was not observed in fluid solution. Upon exposure to the vapor of polar volatile organic compounds (VOC), this photoluminescence was significantly red-shifed. This process was fully reversible when the VOC-incorporated membrane was dried in air. The dramatic and reversible changes in the emission spectra made the Nafion-supported complex as an interesting sensor candi-date for polar VOC.
