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91.
BeQ2衍生物中金属配体间相互作用对前线分子轨道和非线性光学性质影响的理论研究 总被引:1,自引:0,他引:1
采用从头算HF及密度泛函理论(DFT)B3LYP方法对8-羟基喹啉铍(BeQ2)及其取代衍生物Be(MQ)2,Be(CNQ)2的稳定结构及结合能进行计算.在此基础上,系统分析了前线分子轨道组成及体系非线性光学系数的变化.计算结果表明,金属-配体间的相互作用使非线性光学系数增大,且γ比β增大得多;CH3和CN的推拉电子取代均使结合能降低,电子离域性增强,非线性光学性质得以改善. 相似文献
92.
Qian Chu Guang-Xiang Liu Taka-aki Okamura Yong-Qing Huang Wei-Yin Sun Norikazu Ueyama 《Polyhedron》2008
Self-assembly of a new carboxylate containing ligand, N-(3-carboxyphenyl)iminodiacetic acid (H3L), with Cd(II) and Co(II) salts under different reaction pH results in the formation of four new coordination polymers, namely [Cd(HL)(H2O)] (1), [Co(HL)(H2O)] (2), [Cd(HL)(H2O)4] (3) and [Cd3(L)2(H2O)9] · 7H2O (4). Single crystal X-ray diffraction analysis indicates that 1 and 2 are isomorphous and isostructural with a 2D wave-like network structure, while 3 has a 1D zigzag chain structure. The complexes 1–3 were obtained at low pH (<7) which makes the ligands only partly deprotonated. However, complex 4, obtained at pH 7 with all the carboxylate groups deprotonated, exhibits a 2D network structure. The results suggest that the reaction pH is one of the key factors in the formation of the coordination architectures. In addition, the photoluminescence properties of the free ligand (H3L) and complexes 1, 3 and 4 were studied in the solid state at room temperature. Moreover, the magnetic property of complex 2 was investigated. 相似文献
93.
Yong-Qing Chen 《International Journal of Theoretical Physics》2002,41(9):1795-1802
The simple coherent state of the OSP(2,1) superalgebra is constructed and its properties are discussed in detail. The matrix elements of the OSP(2,1) generators in the coherent state space are calculated. The new form for inhomogeneous differential realization of the OSP(2,1) superalgebra is given. 相似文献
94.
Yong-Qing Chen 《International Journal of Theoretical Physics》2006,45(9):1624-1629
One-parameter homogeneous differential realization of the SPL(2,1) superalgebra on the space of homogeneous polynomials and the corresponding boson–fermion realization are studied. The parameter α may be related to the interaction parameter U in one exactly solvable model for correlated electrons.The author was supported financially by Shenzhen Institute of Information Technology grant No. LG-060109.
PACS: 12.60.Jv, 03.65.FD 相似文献
95.
Yong-Qing Yang 《Natural product research》2016,30(14):1628-1632
The previously proposed structure for a tetrahydrofuranol isolated from the leaves of Michelia compressa var. lanyuensis (Magnoliaceae) was synthesised in an enantiopure form using diethyl D-tartarate as the starting material. The synthetic sample showed spectroscopic data incompatible with those for the natural product and thus unequivocally disproved the previously assigned structure. 相似文献
96.
New metal-organic frameworks with large cavities: selective sorption and desorption of solvent molecules 总被引:1,自引:0,他引:1
Wang Y Huang YQ Liu GX Okamura TA Doi M Sheng YW Sun WY Ueyama N 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(26):7523-7531
Five novel transition metal complexes [Cd(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (1), [Cu(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (2), [Ni(II) (3)(tpba-2)(2)(SCN)(6)].6 THF.3 H(2)O (3), [Cd(II) (2)(tpba-2)(SCN)(3)]ClO(4) (4), [Cu(I) (3)(SCN)(6)(H(3)tpba-2)] (5) [TPBA-2 = N',N',N'-tris(pyrid-2-ylmethyl)-1,3,5-benzenetricarboxamide, THF=tetrahydrofuran] were obtained by reactions of the corresponding transition metal salts with TPBA-2 ligand in the presence of NH(4)SCN using layering or solvothermal method, respectively. The results of X-ray crystallographic analysis showed that complexes 1, 2 and 3 are isostructural and have the same 2D honeycomb network structure with Kagomé lattice, in which all the M(II) (M = Cd, Cu, Ni) atoms are six-coordinated, and the TPBA-2 ligands adopt cis,cis,cis conformation while the thiocyanate anions act as terminal ligands. Capsule-like motifs are found in 1, 2 and 3, in which six THF molecules are hosted, and the results of XPRD and solid-state (13)C NMR spectral measurements showed that the compound 1 can selectively desorb and adsorb THF molecules occurring along with the re-establishment of its crystallinity. In contrast to 1, 2 and 3, complex 4 has different 2D network structure, resulting from TPBA-2 ligands with cis,trans,trans conformation, thiocyanate anions serving as end-to-end bridging ligands, and the incomplete replacement of perchlorate anions, which further link the 2D layers into 3D framework by the hydrogen bonds. In complex 5, the Cu(II) atoms are reduced to Cu(I) during the process of solvothermal reaction, and the Cu(I) atoms are connected by thiocyanate anions to form a 3D porous framework, in which the protonated TPBA-2 ligands are hosted in the cavities as templates. 相似文献
97.
SA Hudson KJ McLean S Surade YQ Yang D Leys A Ciulli AW Munro C Abell 《Angewandte Chemie (International ed. in English)》2012,51(37):9311-9316
Pieces of the puzzle: The first fragment-based approach was used to target cytochrome?P450 enzymes (CYPs) for drug development. The experiments provide new insights into the binding site of the essential Mycobacterium tuberculosis CYP121 enzyme, and resulted in a promising novel lead compound based on fragment merging. 相似文献
98.
Yong-Qing Chen 《International Journal of Theoretical Physics》2013,52(3):980-986
One-parameter general coherent state of the gl(2,1) superalgebra is constructed. Its properties are discussed in detail. One-parameter matrix elements of the gl(2,1) generators in the one-parameter general coherent-state space are calculated. 相似文献
99.
100.
正确地对药物分子进行化学命名是药物化学教学中非常重要的部分。对于含有标记氢的药物分子的命名一直是药物化学教学中的难点。将药物化学教材中含有标记氢的化合物进行了归类,并分别举例来分析它们的命名。 相似文献