Ultrafast Excited-State Proton Transfer of 2-(2‘-Hydroxyphenyl)benzothiazole: Theoretical Analysis of the Skeletal Deformations and the Active Vibrational Modes

Vivie-Riedle, Regina de; Waele, Vincent de; Kurtz, L. und Riedle, Eberhard (Dezember 2003): Ultrafast Excited-State Proton Transfer of 2-(2‘-Hydroxyphenyl)benzothiazole: Theoretical Analysis of the Skeletal Deformations and the Active Vibrational Modes. In: Journal of Physical Chemistry A, Bd. 107, Nr. 49: S. 10591-10599

Abstract

The involvement of skeletal deformations in the ultrafast excited-state proton transfer of 2-(2'-hydroxyphenyl)-benzothiazole (HBT) and the identification of the vibrational modes active in the process are reported. A multidimensional ab initio calculation of ground and excited states at the HF/DFT and CIS/TDDFT level renders the relevant portions of the potential energy surfaces around the minimum-energy path connecting the enol and keto configuration. The frequencies and potential energy distributions of the normal modes and the corresponding deformations of the molecule are calculated for all minimum-energy geometries. Along the minimum-energy path, the nuclear deformation is projected onto the relevant normal modes. This normal-mode analysis shows that mainly five low-frequency in-plane vibrations are associated with the electronic rearrangement and the transfer of the proton. The theoretical findings are in quantitative agreement with the experimental study presented in the accompanying paper.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Physik
• Themengebiete: 500 Naturwissenschaften und Mathematik > 530 Physik
• ISSN: 1089-5639
• Sprache: Englisch