Environmental effects on electronic absorption spectra using DFT: An organic and positively charged fused polycyclic chromophore as a case study

Finally, the importance of the vibronic structure to simulate the experimental band shape will be considered focusing on the first electronic transition, and computing ground and first excited states optimized structures together with harmonic frequencies at DFT and TD-DFT level, respectively. The good agreement obtained between computed and experimental spectra confirms the good quality of both the optimized geometries and the harmonic force fields.