Quertinmont Jean, Champagne Benoît, Castet Frédéric, Hidalgo Cardenuto Marcelo
†Laboratoire de Chimie Théorique, Unité de Chimie Physique Théorique et Structurale, University of Namur, rue de Bruxelles, 61, B-5000 Namur, Belgium.
‡Institut des Sciences Moléculaires (ISM), Université de Bordeaux, UMR 5255 CNRS, Cours de la Libération 351, F-33405 Talence Cedex, France.
J Phys Chem A. 2015 May 28;119(21):5496-503. doi: 10.1021/acs.jpca.5b00631. Epub 2015 Mar 18.
The first hyperpolarizability of the four trans forms of a dithienylethene indolinooxazolidine biphotochrome in acetonitrile solution has been evaluated by using two solvation models, an explicit and an implicit one. The implicit solvation model is the integral equation formalism of the polarizable continuum model (IEF-PCM), whereas in the explicit one, the solvent molecules are represented by point charges, of which the positions have been generated by Monte Carlo simulations whereas the solute is treated quantum mechanically. At optical frequencies, first hyperpolarizabilities calculated with the implicit solvation model are usually larger than those obtained with the multiscale approach. However, both approaches predict similar contrasts, indicating that implicit solvation models such as IEF-PCM are well-suited to describe the variations in the NLO responses of molecular switches. In addition, the analysis of the contrasts of first hyperpolarizabilities shows that the biphotochrome can act as a three-state NLO switch.
通过使用两种溶剂化模型（一种显式模型和一种隐式模型），对二噻吩乙烯吲哚啉恶唑烷双光致变色化合物的四种反式异构体在乙腈溶液中的第一超极化率进行了评估。隐式溶剂化模型是极化连续介质模型的积分方程形式（IEF-PCM），而在显式模型中，溶剂分子由点电荷表示，其位置通过蒙特卡罗模拟生成，而溶质则采用量子力学方法处理。在光学频率下，用隐式溶剂化模型计算得到的第一超极化率通常大于用多尺度方法得到的结果。然而，两种方法预测的对比度相似，这表明诸如IEF-PCM之类的隐式溶剂化模型非常适合描述分子开关的非线性光学响应变化。此外，对第一超极化率对比度的分析表明，该双光致变色化合物可作为三态非线性光学开关。
