Overtones of νC≡N Vibration as a Probe of Structure of Liquid CHCN, CDCN, and CClCN: Combined Infrared, Near-Infrared, and Raman Spectroscopic Studies with Anharmonic Density Functional Theory Calculations.

The νCN band (νC≡N) is a sensitive probe of the state of molecules with nitrile groups. Hence, physicochemical properties of acetonitrile and its derivatives have been frequently investigated by means of vibrational (IR and Raman) spectroscopy. Near-infrared (NIR) spectroscopy combined with high-level quantum mechanical calculations offers deeper physical insight into the structure of liquid nitriles not available from the fundamental region.

The Effect of Chain Length on Mid-Infrared and Near-Infrared Spectra of Aliphatic 1-Alcohols.

Effect of the chain length on mid-infrared (MIR) and near-infrared (NIR) spectra of aliphatic 1-alcohols from methanol to 1-decanol was examined in detail. Of particular interest were the spectra-structure correlations in the NIR region and the correlation between MIR and NIR spectra of 1-alcohols. An application of two-dimensional correlation analysis (2D-COS) and chemometric methods provided comprehensive information on spectral changes in the data set.

MIR and NIR group spectra of n-alkanes and 1-chloroalkanes.

Numerous attempts were undertaken to resolve the absorption originating from different parts of alkanes. The separation of the contributions from the terminal and midchain methylene units was observed only in the spectra of solid alkanes at low temperatures. On the other hand, for liquid alkanes this effect was not reported as yet.