Push-pull conjugated molecules

Bartkowiak, W., Zalesny, R., Leszczynski, J. Relation between bond-length alternation and two-photon absorption of push-pull conjugated molecules A quantum-cheiriical study. Chem. Phys. 287, 103-112 (2003)... 

Bouchy, A., Rinaldi, D., and Rivail, J.-L., Solvent effect on intramolecular hydrogen bonds in push-pull conjugated molecules, Int. J. Quantum Chem., 96, 273-281 (2004). 

Due to the fact that the first hyperpolarizability involves multiple virtual excited states (O Eq. 11.68), the property has proven to be more sensitive to electron correlation effects than the polarizability (Christiansen et al. 2006). Molecules with push-pull conjugated structures are often characterized by large first hyperpolarizabilities. Due to the problems facing many... 

Bishop, D.M., Champagne, B., Kirtman, B. Relationship between static vibrational and electronic hyperpolarizabilities of rr-conjugated push-pull molecules within the two-state valence-bond charge-transfer model. J. Chem. Phys. 109, 9987-9994 (1998)... 

In this contribution we review the connection between the nonlinear optical (NLO) response and the solvatochromic behavior of the important class of organic molecules, namely donor-acceptor -tr-conjugated compounds (D-tr-A). In these compounds, also called push-pull chromophores, an electron-donating group D is conjugated to an electron-acceptor substituent A through a system of the localized tr-bonds (Scheme 1). It is well established that such compounds exhibit the following properties [1-7] ... 

Apart from calculations at the ab initio level, the TDHF scheme has also been used with semi-empirical Hamiltonians. This makes it possible to calculate larger molecules while partially accounting for electron correlation effects. Indeed, when estimating the dynamic first hyperpolarizability of reference push-pull rr-conjugated... 

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