Electronic structure investigations of 4-aminophthal hydrazide by UV–visible, NMR spectral studies and HOMO–LUMO analysis by ab initio and DFT calculations (original) (raw)
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ELECTRONIC AND THERMODYNAMIC PROPERTIES OF NAOH
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An ab initio study of the equilibrium geometry and vibrational frequencies of hydrazine
Chemical Physics Letters, 2002
Accurate optimized equilibrium geometries, harmonic frequencies and rotational constants of the gauche conform (C 2 symmetry) of hydrazine ðN 2 H 4 Þ have been calculated employing a large series of basis sets and several ab initio methods. Our best estimate computed equilibrium geometries are r NN ¼ 1:434 A A, r NH i ¼ 1:013 A A, r NHo ¼ 1:010 A A, h NNH i ¼ 111:3°, h NNHo ¼ 106:8°and h H i NNHo ¼ 89:7°. These predictions were used as reference in the analysis of the experimental and theoretical data, and we expected that the present results could guide future investigations in this direction.
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Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2012
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