Raman Spectra of Phenylacetylene in Acetonitrile and Methylcyclohexane at Low Temperatures. 2. Structural Order and Vibrational Relaxation in Frozen Matrices at 77 K

Raman spectra of the ν S (C⋮C) stretching mode of phenylacetylene (PA) dissolved in acetonitrile and methylcyclohexane have been recorded at 77 K and compared with spectra in the liquid solutions at room temperature [Kołodziejski, M.; Waliszewska, G.; Abramczyk, H. J. Phys. Chem. A 1998, 102, 1918]. Substantial narrowing of spectra in frozen matrices at low temperatures leads to revealing of vibrational structure. The results given in this paper are a spectacular example of monitoring structural order going from liquid solutions to frozen matrices at low temperatures by Raman spectroscopy.