Electronic-vibrational excitations of a hydrogen-bonded molecule in supersonic expansions: 1,4-dihydroxyanthraquinone and its deuterated derivatives

Research output: Contribution to journalArticlepeer-review

Abstract

In this paper we report the results of an experimental study of the S0 → S1 and S1 → S0 transitions of 1,4-dihydroxyanthraquinone [H,H] and its deuterated derivatives [H,D] and [D,D], explored by laser spectroscopy in seeded, pulsed, supersonic expansions of He and of Ar. We were able to provide quite detailed information on the vibrational level structure. Out of the twenty-five A1 totally symmetric vibrations, we were able to identify sixteen A1 modes in S0 and seventeen A1 modes in S1. In addition, we observed nine B2 out-of-plane modes involved in vibronic coupling. Evidence for the strengthening of the hydrogen bond upon S0 → S1 electronic excitation was inferred from the increase of the frequencies of the vibrational modes of the {A figure is presented} rings upon electronic excitation, as well as from the large blue deuterium isotopic shifts, which originate from the weakening of the ν(OH)] stretching upon S0 → S1 excitation. On the basis of the analysis of energetics and the relative intensities of overtones and of combination bands, we concluded that electronic excitations to S1 result in small configurational changes. No spectroscopic evidence for nuclear motion in a double-well potential of the hydrogen bond in the S1 state could be inferred. Furthermore, our spectroscopic data do not provide any evidence for intramolecular H-atom transfer in the electronically-vibrationally excited states of this isolated molecule.

Original languageEnglish
Pages (from-to)1-18
Number of pages18
JournalChemical Physics
Volume73
Issue number1-2
DOIs
StatePublished - 1 Dec 1982

Fingerprint

Dive into the research topics of 'Electronic-vibrational excitations of a hydrogen-bonded molecule in supersonic expansions: 1,4-dihydroxyanthraquinone and its deuterated derivatives'. Together they form a unique fingerprint.

Cite this