The electronic structure for C 60 was semi empirically investigated by using MD (molecular dynamics) and MNDO (modified neglect of diatomic overlap) approach of quantum chemistry.Especially,taking both σ and ...The electronic structure for C 60 was semi empirically investigated by using MD (molecular dynamics) and MNDO (modified neglect of diatomic overlap) approach of quantum chemistry.Especially,taking both σ and π orbitals into account,one electron energy levels,those symmetries and π orbital occupancies as well as electron excitation energies for different select rules,cohesive energy,ionization energies and electronic affinity forces were calculated.The obtained molecular orbital ratio shows a wide separation of σ and π types,and near HOMO and LUMO levels there are π orbitals mainly.The calculated semi empirical calculation results are in good agreement with experimental and ab initio calculation data.展开更多
The coordination polymer,[Mn3（L） 2（adip） 3]·2H2O（L = 2-（4-fluorophenyl） -1H-imidazo[4,5-f] [1,10]phenanthroline and H2adip = adipic acid） ,has been synthesized under hydro-thermal conditions and character...The coordination polymer,[Mn3（L） 2（adip） 3]·2H2O（L = 2-（4-fluorophenyl） -1H-imidazo[4,5-f] [1,10]phenanthroline and H2adip = adipic acid） ,has been synthesized under hydro-thermal conditions and characterized by elemental analysis,IR and single-crystal X-ray diffraction. It crystallizes in triclinic,space group P1^- with a = 8.4085（11） ,b = 11.1273（14） ,c = 14.5758（18） ,α = 78.528（2） ,β = 75.425（2） ,γ = 78.143（2） °,V = 1276.0（3） A^3,Z = 1,C56H50F2Mn3N8O14,Mr = 1261.86,Dc = 1.642 g/cm^3,F（000） = 647,μ（MoKa） = 0.819 mm^-1,R = 0.0446 and wR = 0.1008. The backbones of the two types of adip dianions link the neighboring trinuclear Mn（Ⅱ） clusters to yield a two-dimensional layer structure. The large conjugated L ligands are located on both sides of the two-dimensional layers. Additionally,the O-H···O,O-H···N and N-H···O hydrogen bonds further stabilize the structure.展开更多
The new cluster[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)_6]has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid.The crystal and molecular structures were determined by the X-ray diffrac...The new cluster[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)_6]has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid.The crystal and molecular structures were determined by the X-ray diffraction method.It crystallizes in the orthorhombic space group Pnna with cell parameters:Mr=1361.6,a=13.792(4), b=17.957(3),c=20.974(9) ,V=5194(2) ~3,Z=4,Dc=1.74/cm^3,F(OOO)=2704,μ(MoK ) =11.0/cm,R=0.074.展开更多
The present paper represents the electronic structures of the cluster C60 and its derivatives C60H60 and C60F60 with FOOT-type of structure. On the basis of the total energies and molecular orbital energies from CNDO/...The present paper represents the electronic structures of the cluster C60 and its derivatives C60H60 and C60F60 with FOOT-type of structure. On the basis of the total energies and molecular orbital energies from CNDO/2 calculations the clusters' stabilities, electronic configurations and charge distributions are discussed. The calculation results and discussion are very beneficial to understanding physical and chemical properties of the cluster C60 and its derivatives.展开更多
本文采用量子化学密度泛函理论的B3LYP/6-31G*方法,对C24和B12N12团簇的12种异构体进行了优化,并对它们的几何构型、振动频率、核独立化学位移(NICS)和结合能进行了理论探讨, 比较了C24和B12N12团簇结构的稳定性。研究表明:C24团簇的最...本文采用量子化学密度泛函理论的B3LYP/6-31G*方法,对C24和B12N12团簇的12种异构体进行了优化,并对它们的几何构型、振动频率、核独立化学位移(NICS)和结合能进行了理论探讨, 比较了C24和B12N12团簇结构的稳定性。研究表明:C24团簇的最稳定几何构型为类石墨结构d,B12N12团簇的最稳定结构为4/6笼状结构g。C24异构体的稳定性大小顺序为d > b > f > c > a > e。B12N12团簇异构体稳定性大小顺序为a > f> c> d > e >b。展开更多
文摘The electronic structure for C 60 was semi empirically investigated by using MD (molecular dynamics) and MNDO (modified neglect of diatomic overlap) approach of quantum chemistry.Especially,taking both σ and π orbitals into account,one electron energy levels,those symmetries and π orbital occupancies as well as electron excitation energies for different select rules,cohesive energy,ionization energies and electronic affinity forces were calculated.The obtained molecular orbital ratio shows a wide separation of σ and π types,and near HOMO and LUMO levels there are π orbitals mainly.The calculated semi empirical calculation results are in good agreement with experimental and ab initio calculation data.
基金Supported by the Institute Foundation of Siping City (No.2009011)
文摘The coordination polymer,[Mn3（L） 2（adip） 3]·2H2O（L = 2-（4-fluorophenyl） -1H-imidazo[4,5-f] [1,10]phenanthroline and H2adip = adipic acid） ,has been synthesized under hydro-thermal conditions and characterized by elemental analysis,IR and single-crystal X-ray diffraction. It crystallizes in triclinic,space group P1^- with a = 8.4085（11） ,b = 11.1273（14） ,c = 14.5758（18） ,α = 78.528（2） ,β = 75.425（2） ,γ = 78.143（2） °,V = 1276.0（3） A^3,Z = 1,C56H50F2Mn3N8O14,Mr = 1261.86,Dc = 1.642 g/cm^3,F（000） = 647,μ（MoKa） = 0.819 mm^-1,R = 0.0446 and wR = 0.1008. The backbones of the two types of adip dianions link the neighboring trinuclear Mn（Ⅱ） clusters to yield a two-dimensional layer structure. The large conjugated L ligands are located on both sides of the two-dimensional layers. Additionally,the O-H···O,O-H···N and N-H···O hydrogen bonds further stabilize the structure.
基金Work supported by the National Natural Science Foundation of China(NNSFC)
文摘The new cluster[Mo_4(μ_3-O)_2O_4Cl_2(o-CH_3C_6H_4COO)_6]has been prepared by the reaction of molybdenum pentachloride and o-methylbenzoic acid.The crystal and molecular structures were determined by the X-ray diffraction method.It crystallizes in the orthorhombic space group Pnna with cell parameters:Mr=1361.6,a=13.792(4), b=17.957(3),c=20.974(9) ,V=5194(2) ~3,Z=4,Dc=1.74/cm^3,F(OOO)=2704,μ(MoK ) =11.0/cm,R=0.074.
文摘The present paper represents the electronic structures of the cluster C60 and its derivatives C60H60 and C60F60 with FOOT-type of structure. On the basis of the total energies and molecular orbital energies from CNDO/2 calculations the clusters' stabilities, electronic configurations and charge distributions are discussed. The calculation results and discussion are very beneficial to understanding physical and chemical properties of the cluster C60 and its derivatives.
文摘本文采用量子化学密度泛函理论的B3LYP/6-31G*方法,对C24和B12N12团簇的12种异构体进行了优化,并对它们的几何构型、振动频率、核独立化学位移(NICS)和结合能进行了理论探讨, 比较了C24和B12N12团簇结构的稳定性。研究表明:C24团簇的最稳定几何构型为类石墨结构d,B12N12团簇的最稳定结构为4/6笼状结构g。C24异构体的稳定性大小顺序为d > b > f > c > a > e。B12N12团簇异构体稳定性大小顺序为a > f> c> d > e >b。
