Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence f...Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.展开更多
The structure and coordination properties of N,N bis(N methylene 2 pyrrolidinyl)alanine have been studied. The results show that the title compound is stable, the geometry calculated by AM1 is in good agreement with e...The structure and coordination properties of N,N bis(N methylene 2 pyrrolidinyl)alanine have been studied. The results show that the title compound is stable, the geometry calculated by AM1 is in good agreement with experimental results. The atoms of O(1),O(15), O(19),O(20) in the molecule bond easily with metallic atoms. So the title compound can form stable complex with rare earth metal ions.展开更多
The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA wi...The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)E·H2O 1 and [CoL2](NO3)E·H2O 2 as isolatable products (L= N-(1- benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12)A, β = 135.219(4)°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ(MoKa) = 0.876 mm^-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I 〉 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2)A, β = 130.099(3)°, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) A3 Z = 4, Dc = 1.543 g/cm^3,μ(MoKa) = 0.722 mm^-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- (or NO3^-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.展开更多
基金National Natural Science Foundation of China !(Grant No. 29871029)Laboratory of Rare Earth Chemistry and Physics, Changchun
文摘Valence of elements in HgBa_2Ca_(n-1)Cu_nO_(2n+2+δ)(n=1, 2, 3, 4) (both argon and oxygen annealed samples) were calculated. The result indicated for both argon and oxygen annealed samples, Hg had the lowest valence for the highest Tc sample. For fixed n, the valence of Cu in oxygen annealed samples was larger than that in argon annealed samples, indicating that oxygen annealed samples produce more carriers than argon annealed samples.
文摘The structure and coordination properties of N,N bis(N methylene 2 pyrrolidinyl)alanine have been studied. The results show that the title compound is stable, the geometry calculated by AM1 is in good agreement with experimental results. The atoms of O(1),O(15), O(19),O(20) in the molecule bond easily with metallic atoms. So the title compound can form stable complex with rare earth metal ions.
基金the National Natural Science Foundation of China (20425313)the Natural Science Foundation of Fujian Province (2005HZ01-1, 2006L2005, 2006F3135, 2006J0183)
文摘The reactions of Co(C1O4)2·6H2O and Co(NO3)2.6H2O with the di-Schiff base ligand N,N'-bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine (LA) in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2](ClO4)E·H2O 1 and [CoL2](NO3)E·H2O 2 as isolatable products (L= N-(1- benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine), where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1: monoclinic, space group P21/c, a = 11.9214(10), b = 23.5828(17), c = 14.0387(12)A, β = 135.219(4)°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1(4) A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ(MoKa) = 0.876 mm^-1, F(000) = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections (I 〉 2σ(I)). Crystal data for complex 2: monoclinic, space group P21/c, a = 18.2162(16), b = 10.0610(6), c = 18.593(2)A, β = 130.099(3)°, C22H30CoN10O7, Mr = 605.49, V = 2606.5(4) A3 Z = 4, Dc = 1.543 g/cm^3,μ(MoKa) = 0.722 mm^-1, F(000) = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections (I 〉 2σ(I)). X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- (or NO3^-) groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.