Vulpius D, Geipel G, Bernhard G. Excited-state proton transfer of 3-hydroxybenzoic acid and 4-hydroxybenzoic acid.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010;
75:558-562. [PMID:
20031478 DOI:
10.1016/j.saa.2009.11.016]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 11/06/2009] [Accepted: 11/10/2009] [Indexed: 05/28/2023]
Abstract
The excited-state proton transfer of 3-hydroxybenzoic acid and 4-hydroxybenzoic acid was studied by time-resolved laser-induced fluorescence spectroscopy with ultra-short laser pulses. The excited-state reactions were identified in aqueous media as a function of the pH value. Apart from the well-known inversion of the ordinary dissociation properties of these compounds, new species were found which exist only in the excited-state resulting from a temporal and reversible annihilation of the aromatic bond system. These species and their reaction mechanisms were detected by their absorption and fluorescence spectra.
Collapse