A novel set-up to investigate the low-frequency spectra of aqueous solutions at high hydrostatic pressure
L Knake1, H Vondracek1, M Havenith1
1Department of Physical Chemistry II, Ruhr-University Bochum, 44780 Bochum, Germany.
Abstract:
We present a novel setup to investigate the low frequency (THz/FIR) spectra of an aqueous solution under high hydrostatic pressure (HHP). By integration of a diamond anvil cell into a THz Fourier transform spectrometer, we are able to record the absorption of bulk water in the pressure range from 1 bar to 10 kbar. The difference in intensity can directly be compared to the difference in extinction coefficients. The spectroscopic data reveal a blue shift of the H-bond stretch vibration at 180 cm-1, which is evidence of changes in the H-bond network dynamics.
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