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1

Crystal Structure and Quantum Chemical Calculations on o-Hydroxyacetophenone Phenylhydrazone

Jian F. F., Li Y. F., Yang X. Y., Zhao P. S., Xiao H. L.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 8

1597-1597

EN

o-Hydroxyacetophenone phenylhydrazone has been synthesized and characterized by elemental analysis, IR and electronic spectroscopy. The X-ray crystal structure study shows that the compound contains two crystallographically independent molecules in the asymmetric unit and crystallizes in the monoclinic system, space group P21/c, with Mr =226.27 (C14H14N2O), a = 13.433(3), b = 10.738(2), c = 18.351(7) Capital A, beta = 114.44(2)°, V = 2409.8(12) Capital A 3, Z = 8, Dc = 1.247 Mg/m3, F (000) = 960, mi (Mo K) = 0.080 mm–1, R = 0.0638, wR = 0.1535. Ab initio calculations of the structure, atomic charge distributions, natural bond orbital analysis and thermodynamic functions of the title compound were performed at HF/6-311G** and B3LYP/6-311G** levels of theory. Electronic absorption spectra were calculated by the time-dependent density functional theory (TD-DFT). Vibrational frequencies were predicted, as signed and compared with the experimental values. The calculation of the second order optical nonlinearity was carried out and the molecular hyperpolarizability of 3.332×10–30 esu was predicted.

2

Quantum Chemistry Studies on Bis(p-aminobenzoato)–lead(II) Complex [Pb(C6H4NH2COO)2]

Zhao P., Xu J., Li R., Zhang W., Cai Z.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 1

85-93

EN

The title complex, bis(p-aminobenzoato)–lead(II) [Pb(C6H4NH2COO)2], has been optimized at B3LYP/LANL2DZ level of theory and the calculated results show that the lead(II) ion adopts a four-coordinate geometry. The analyses of NPA and Mulliken atomic charge distributions indicate that during the process of the formation of this compound, both aminobenzoato ligands transfer their negative charges to the lead(II) ion. The lead atom and oxygen atoms form covalent bonds by using their 6p and 2p orbitals, respectively. The calculations of electronic spectra of the title complex show that there exist four absorption bands and the electronic transitions are mainly derived from the contributions ofboth an intraligand* transition and ligand-to-metal charge transfer (LMCT) transitions. The thermodynamic properties of the studied compound at different temperatures have been calculated and the corresponding relations between the properties and temperatures have also been obtained. The calculation of the second order optical nonlinearity has been carried out, and the molecular hyperpolarizability of the title complex is 7.61379x10–30 esu.

3

Experimental and Theoretical Study on 3-Benzyl-4-phenyl-1,2,4-triazole-5-thione

Zhao P., Li R., Xu J., Zhang W.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 8

1495-1503

EN

The 3-benzyl-4-phenyl-1,2,4-triazole-5-thione was synthesized and examined by elementary analysis, IR and electronic spectra. Density functional theory calculations of the structure, natural bond orbitals and thermodynamic functions of the title compound were performed at B3LYP/6-311G** level of theory. Vibrational frequencies were predicted, assigned and compared with the experimental data, and they are supported by the experimental data. Electronic absorption spectrawere calculated by the time-dependent density functional theory (TD-DFT), which indicates that the two absorption bands are mainly derived from the contribution of bands *. The calculation of the second order optical nonlinearity was carried out, giving value of molecular hyperpolarizability equal to 4.025ź10–30 esu. These calculated results were also compared with results obtained for a similar molecule, 4-phenyl-3-[(1,2,4-triazol-1-yl)methyl]-triazole-5-thione, reported earlier by this group.

4

Experimental and Theoretical Study on4-Phenyl-3-[(1,2,4-triazol-1-yl)methyl]-triazole-5-thione

Jian F., Zhao P., Bai Z., Cai Z.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 2

325-333

EN

The title compound, 4-phenyl-3-[(1,2,4-triazol-1-yl)methyl]-triazole-5-thione, was synthesized and characterized by elemental analysis, IR and electronic spectra. Density functional theory calculations of the structure, natural bond orbital and thermodynamic functions of the title compound were performed at B3LYP/6-311G** level of theory. Vibrational frequencies were predicted, assigned, compared with the experimental values, and they are supported each other. Electronic absorption spectra were calculated by the time-dependent density functional theory (TD-DFT), which indicates that the two absorption bands aremainly derived from the contribution of bands pi--pi*. The calculation of the second order optical nonlinearity was carried out with PM3 semi-empirical method that resulted in the molecular hyperpolarizability equal to 4.397x10-30 esu.