1. Static electronic and vibrational first hyperpolarizability of meta-dinitrobenzene as studied by quantum chemical calculations
- Author
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Zaleśny, R., Wójcik, G., Mossakowska, I., Bartkowiak, W., Avramopoulos, A., and Papadopoulos, M.G.
- Subjects
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NITROBENZENE , *POLARIZABILITY (Electricity) , *ELECTRIC properties of materials , *MECHANICAL behavior of materials , *NONLINEAR optics , *QUANTUM chemistry , *DENSITY functionals , *WAVE functions - Abstract
Abstract: In the present study, we report on the results of computations of the electronic and the vibrational contributions to the static first hyperpolarizability of meta-dinitrobenzene molecule. It turned out that the electron correlation effects are much more important for reliable prediction of the electronic counterpart than for determining vibrational corrections: value is increased by about 500% passing from the HF to the CCSD(T) level of theory. The preliminary assessment of density functional theory in determination of hyperpolarizabilities shows that harmonic contributions to , contrary to the purely electronic contributions, are substantially underestimated in comparison with the wave function theory results. Another important finding of this study is that long-range corrected functionals tend to improve upon traditional functionals both in determining electronic as well as vibrational hyperpolarizabilities. It is also demonstrated that the vibrations of the nitro groups have a predominant influence on the vibrational contributions to . The mechanical and electrical anharmonicity correction terms to the vibrational hyperpolarizability were found to be substantially larger than the lowest-order harmonic term. [Copyright &y& Elsevier]
- Published
- 2009
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