Vibrational analysis of <i>trans</i>‐stilbene in the excited singlet state by time‐dependent density functional theory: calculations of the Raman, infrared, and fluorescence excitation spectra

Abstract

Abstract Time‐dependent density functional theory (TD‐DFT), together with the analytic calculation of gradients and numerical calculation of the Hessian matrix, has been applied to calculate the Raman, infrared, and fluorescence excitation spectra of trans ‐stilbene ( t SB) in the lowest excited singlet (S 1 ) state. The TURBOMOLE program package has been used at the B3LYP/6‐311 + + G(d,p) level, and the results obtained are found useful for analyzing a wide range of experimental results so far obtained by many authors. The advantage of TD‐DFT over other methods in performing such calculations seems to lie in its capability of treating electron correlation more appropriately with computational resources currently available. Copyright © 2008 John Wiley &amp; Sons, Ltd.