Abstract
In models based on valence bond theory for predicting nonlinear optical properties of push-pull molecules, the wave functions representing resonance structures are assumed to be orthogonal. We have extended the two-state valence bond charge-transfer model to include non-zero overlap integrals. The resulting model leads to analytic formulae for the polarizability and hyperpolarizabilities, which are related to the overlap and other molecular parameters. In particular we report, as a function of the overlap: (i) relatively weak dependence of the first-order polarizability; (ii) significant variations in both the magnitude and the shape of the response curves corresponding to the second- and third-order polarizabilities. This result may be of relevance in the context of optical switching effects induced by chemical changes (related to the overlap) rather than the more conventional field-induced effect.
Original language | English (US) |
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Pages (from-to) | 1805-1811 |
Number of pages | 7 |
Journal | Molecular Physics |
Volume | 101 |
Issue number | 12 |
DOIs | |
State | Published - Jun 2003 |
Externally published | Yes |
ASJC Scopus subject areas
- Biophysics
- Molecular Biology
- Condensed Matter Physics
- Physical and Theoretical Chemistry