Analysis of liquid methanol-d3 by Raman spectroscopy and density functional calculations

CHED 943

Tegan S. Presley, tpresley01@hamline.edu and Daniel M. Besemann, dbesemann@hamline.edu. Department of Chemistry, Hamline University, 1536 Hewitt Ave, St. Paul, MN 55104
In solution, methanol self-associates to form a variety of hydrogen-bonded molecular clusters. Determination of the nature of these clusters using available spectroscopic data is not straightforward. This work examines the dependence of O-H stretch vibrational frequencies and transition strengths in the various microenvironments (positions within a cluster) via density functional theory (DFT) calculations. Raman spectra are also acquired for differing concentrations of CD3OH in CCl4 solvent, allowing the observation of growth and disappearance of various spectral features. The experimental Raman lineshapes are compared to the DFT results. A number of different microenvironments are identified that are consistent with both the experimental and computational data. Results are also compared to previous infrared absorption data of CD3OH in CCl4.