Ethanol hydrates and solid solution formed by gas condensation: an in situ study by micro-Raman scattering and X-ray diffraction.
Thin films of ethanol-water solid mixtures formed by gas co-condensation are investigated in situ by micro-Raman scattering in the 800-1600 and 2800-3800 cm(-1) spectral regions. Information at the molecular level on the structure is derived from accompanying changes observed in band shapes and vibrational mode frequencies. Depending on the ethanol content, the formation of two distinct ethanol hydrates is spectroscopically characterized, and their structures are independently confirmed by X-ray diffraction measurements. The attribution of the different phases is made in comparison with literature data and in relation with the ethanol phase diagram. Raman characteristic spectral features of ethanol extremely diluted in ice and corresponding to a solid solution regime are reported.
Facq
Sébastien
S
Laboratoire de Physique des Lasers, Atomes et Molécules, Université Lille 1, UMR CNRS 8523, Centre d'Etudes et de Recherches Lasers et Applications, 59655 Villeneuve d'Ascq, France. facq@phlam.univ-lille1.fr
Danède
Florence
F
Chazallon
Bertrand
B
D000431:Ethanol / Q000737:chemistry*; D005740:Gases / Q000737:chemistry; D008567:Membranes, Artificial; D012996:Solutions; D013059:Spectrum Analysis, Raman; D014867:Water / Q000737:chemistry*; D014961:X-Ray Diffraction
D005740:Gases; D008567:Membranes, Artificial; D012996:Solutions; D014867:Water; D000431:Ethanol