Electronic Excitations in Epicocconone Analogues: TDDFT Methodological Assessment Guided by Experiment

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• 作者：Olga A. Syzgantseva ; Vincent Tognetti ; Laurent Joubert ; Agathe Boulang茅 ; Philippe A. Peixoto ; St茅phane Leleu ; Xavier Franck
• 刊名：The Journal of Physical Chemistry A
• 出版年：2012
• 出版时间：August 23, 2012
• 年：2012
• 卷：116
• 期：33
• 页码：8634-8643
• 全文大小：445K
• 年卷期：v.116,no.33(August 23, 2012)
• ISSN：1520-5215

文摘

In this work we present a combined theoretical and experimental study of UV/vis absorption spectra of novel organic chromophores derived from epicocconone. A computational protocol, consistent with experimental findings, is proposed in the framework of time-dependent density functional theory. More precisely, the influence of density functional, basis set, and solvation effects is assessed through theory鈥揺xperiment matching. On the one hand, it is shown that global hybrid functionals fail to describe excitation spectra for the whole training set. On the other hand, range-separated hybrids allow a description of the complete set of epicocconone derivatives on equal footing, while the double-味 basis set is shown to be sufficiently accurate for the screening of the spectroscopic properties in epicocconone analogues. The inclusion of solvent effects within a polarizable continuum model appears to be compulsory to decrease the residual dispersion. State specific solvation, on the contrary, does not provide a significant consistency/accuracy improvement. Besides, conformational transformations in investigated compounds and their influence on electronic absorption spectra are pointed out. A systematic choice of the same conformation for each compound from the training set enhances consistency and accuracy of our theoretical model. Lastly, a TDDFT-based calibration is proposed for prediction of absorption wavelengths in epicocconone analogues.