Effect of pressure on the Raman spectra of methanol-ethanol-water mixture at room temperature

Abstract

We measured Raman spectra for liquid methanol, ethanol, water and their mixture under ambient conditions. We also measured these spectra for wavenumbers in the range 1400-1600 cm −1 for methanol-ethanol (4 : 1) and methanol-ethanol-water (16 : 3 : 1) mixtures as functions of pressure up to 62 kbar at room temperature. We present results for the wavenumber, linewidth and relative intensity of the prominent bands as functions of pressure. These results should be useful for understanding the pressure (hydrostatic) dependence of the Raman spectra of solids.

An investigation of the sol–gel process in ionic liquid–silica gels by time resolved Raman and 1H NMR spectroscopy

“…The additional mode at 1020 cm À1 is attributed to the formation of methanol and assigned to C-O stretching. 27 For a more complete vibrational assignment see Table 1. The small yet detectable changes in the range 1350-1450 cm À1 are assigned to the consumption of formic acid (COH bending) and the concomitant production of methyl formate (CH 3 bending).…”

“…3, where the Raman intensity for the mode at 490 cm À1 Table 1 Selected vibrational modes and corresponding assignments. [26][27][28]29,30 y In this respect, it would also be extremely interesting to investigate the evolution of different local structures by TEM and time-resolved small angle X-ray scattering (SAXS). 32 abruptly increases at t/t gel = 5 in concomitance with a significant volume shrinkage, in contrast to what is observed in ionogels.…”

Recent Advances in linear and nonlinear Raman spectroscopy I

“…Raman spectroscopy, complemented by a pressure cell such as a diamond anvil cell, facilitates investigations of some material properties as demonstrated by Singh et al 289 for methanol-ethanol-water mixtures at room temperature. Data for the pressure dependence of the vibrational transition wavenumbers, line widths, and relative intensities of the Raman bands were reported.…”