Vibrational study of methylamine dimer and hydrated methylamine complexes in solid neon supported by ab initio calculations

For the first time the investigation of water molecule complexed with methylamine (CH3NH2) in solid neon was performed from 80 to 600 0 cm(-1) using Fourier transform infrared spectroscopy. From concentration effects and with the help of theoretical results we have identify several vibrational transitions for CH3NH2 dimer, CH3NH2-H2O, and CH3NH2-(H2O)(2) complexes. For the CH3NH2-H2O complex, where the two submolecules interacting through hydrogen bonding, the infrared (IR) spectral changes (frequencies as well as intensities) indicate that the water playing the role of the proton donor, in agreement with the previous theoretical works. Theoretical calculations at the second-order Moller-Plesset level have been performed to obtain their equilibrium geometries and vibrational spectra at the harmonic level and comparison with experimental data allows us to give structures of observed complexes. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The investigation of water molecule complexed with methylamine (CH3NH2) in solid neon was carried out using Fourier transform infrared spectroscopy from 80 to 600 cm(-1) for the first time. The experimental and theoretical results revealed the importance of hydrogen bonding between water and methylamine in the observed complexes.