THE STRUCTURE OF 4-METHYLPHENOL AND ITS WATER CLUSTER REVEALED BY ROTATIONALLY RESOLVED UV-SPECTROSCOPY USING A GENETIC ALGORITHM APPROACH

Author Institution: Molecular- and Biophysics Group,; Institute for Molecules and Materials, Radboud University; Nijmegen,; NL-6500 GL Nijmegen, The Netherlands; Heinrich-Heine-Universitat, Institut fur; Physikalische Chemie, 40225 Dusseldorf, GermanyThe structure of 4-methylphenol (p-cresol) and its binary water cluster has been elucidated by rotationally resolved laser induced fluorescence spectroscopy. The electronic origins of the monomer and the cluster are split into four subbands by the internal rotation of the methyl group and of the hydroxy group in case of the monomer and the water moiety in case of the cluster. From the rotational constants of the monomer the structure in the S$_{1}$-state could be determined to be distorted quinoidally. The structure of the p-cresol-water cluster is determined to be translinear, with a OO hydrogen bond length of 290 pm in the electronic ground state and of 285 pm in the electronically excited state similar to the hydrogen bonded phenol-water cluster