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Updated: Jul 14, 2026

Proton Transfer and Protein Conformation Dynamics in Photosensitive Proteins by Time-resolved Step-scan Fourier-transform Infrared Spectroscopy
Published on: June 27, 2014
Proton transfer in (HCOOH)2: an IR high-resolution spectroscopic study of the antisymmetric C-O stretch
Markus Ortlieb1, Martina Havenith
1Department of Physical Chemistry II, Ruhr-University Bochum, Universitätsstrasse 150, D-44780 Bochum, Germany.
Abstract:
We report the fully analyzed high-resolution spectrum of the carboxylic acid dimer (HCOOH)2 in the gas phase. High-resolution IR spectra in the region of the antisymmetric C-O stretch vibration have been recorded at 1221.0-1226.7 cm(-1). The data could be fit within experimental uncertainty to a rigid rotor Watson S-reduced Hamiltonian. The vibrational frequency of the C-O vibration is 1225.3430(3) cm(-1). On the basis of the measurement of a tunneling splitting of 0.0158(4)cm(-1) for the lower state and 0.0100(3) cm(-1) for the upper state, we determine a proton-transfer time of 1.0 and 1.7 ns for the ground and the vibrationally excited state, respectively.
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