Mechanism for large first hyperpolarizabilities of phosphonic acid stilbene derivatives

• Published in: Journal of computational chemistry 2002-01, Vol.23 (2), p.291-297
• Main Authors: Calaminici, Patrizia, Jug, Karl, Köster, Andreas M., Arbez-Gindre, Cécile, Screttas, Constantinos G.
• Format: Article
• Language: English
• Subjects: dipole moments; hyperpolarizabilities; polarizabilities; stilbene derivatives
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.10006

This paper presents calculations of dipole moments (μ), static polarizabilities (α), and first hyperpolarizabilities (β) of phosphonic acid stilbene derivatives calculated in the framework of density functional theory. These calculations were performed using a finite field approach implemented in the density functional program ALLCHEM and were of an all‐electron type using local exchange‐correlation functional and specially designed basis sets. The molecular structures have been fully optimized using the semiempirical program MSINDO. Some of the investigated stilbenes have been synthesized very recently while others are described for the first time. Donor and acceptor groups of these analogues have been modified and the influence of these changes on the first hyperpolarizabilities has been investigated. This work demonstrates that the nonlinear optical response β of these compounds increases dramatically when the acceptor moiety is displaced by analogues containing alkali metal groups. A general mechanism for the design of novel nonlinear optical materials with large first hyperpolarizabilities is described. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 291–297, 2002