title: TDDFT study of one- and two-photon absorption properties: donor-pi-acceptor chromophores.
abstract: We report a comprehensive time-dependent density functional theory (TDDFT) study of one-photon and two-photon absorption (OPA and TPA, respectively) spectra for donor-pi-acceptor molecules. The calculated excitation energies were generally shown to be in good agreement with experiment, particularly when compared to results from measurements carried out in a nonpolar solvent, although the oscillator strengths were overestimated in some cases. Calculated TPA cross sections applying the two-state approximation were shown to be highly dependent on the form of the line-shape function used. Although a good agreement with experimental TPA spectra was generally observed, the wide range in the experimentally measured values and lack of systematic experimental data on solvent effects limited a detailed comparison as yet.
authors.affiliation: Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright Patterson Air Force Base, Ohio 45433, USA.
authors.forename: Paul N
authors.initials: PN
authors.lastname: Day
authors.forename: Kiet A
authors.initials: KA
authors.lastname: Nguyen
authors.forename: Ruth
authors.initials: R
authors.lastname: Pachter