INS, DFT and temperature dependent IR investigations of dynamical properties of low temperature phase of choline chloride

- Choline chloride was investigated by INS and IR.
- DFT calculations for solids state model were performed.
- Full vibrational analysis was performed.
- Activation energy for the CH3 group reorientation was obtained.

Within the framework of the research the inelastic neutron scattering and temperature dependent infra-red spectroscopy investigations of the low temperature phase of choline chloride were performed. The infra-red spectra in wavenumber region 4000-80 cm−1 and in a temperature range 9-300 K were collected. The density functional theory calculations with the periodic boundary conditions for determination and description of the normal modes in the vibration spectra of choline chloride were applied. Bands assigned to the CH3 torsional vibration were observed at 288 and 249 cm−1. From the analysis of the temperature dependence of the full-width-at-half-maximum the activation energy for CH3 group reorientation is found to be equal to 1.6 ± 0.2 kcal/mol.