Ab initio calculations of S1 excited state vibrational spectra of benzene, naphthalene and anthracene

摘要: Abstract Normal-mode calculations are presented for the lowest singlet excited states S 1 of benzene, naphthalene and anthracene. Optimized geometries Cartesian harmonic force constants obtained from ab initio at CIS/6-31G, CIS/6-31G ∗ , CIS/6-311G levels analysis is performed in internal coordinates, yielding vibrational frequencies forms normal modes parent molecules their perdeuterated derivatives. The results compared with corresponding properties ground state 0 calculated Hartree-Fock level available experimental data. overall changes molecular geometry spectra upon → excitation small. For benzene we find excellent agreement entire spectrum results. anthracene good limited Our provide predictions types complete these molecules, suggest reassignments several normal-mode to that currently available.