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

• Published in: Journal of molecular structure Vol. 1236; p. 130308
• Main Authors: Soulard, P., Tremblay, B.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2021; Elsevier
• Subjects: ab initio calculations; Human health and pathology; Hydrogen Bond; Infrared Spectroscopy; Life Sciences; Methylamine dimer; Methylamine-water complex; Neon Matrix Isolation; Tissues and Organs; Neon Matrix Isolation; Infrared Spectroscopy; ab initio calculations; Methylamine dimer; Hydrogen Bond; Methylamine-water complex
• ISSN: 0022-2860; 1872-8014; 0022-2860
• DOI: 10.1016/j.molstruc.2021.130308

•First investigation of (CH3N)m-(H2O)n in solid neon from the far to the near IR.•Complementarity of ab initio calculation and experiment to perform analysis.•MA dimer frequencies from Ne matrix very close to the gas phase values.•CH3NH2-H2O hydrogen bonding and a strong observed OH red-shift frequency. For the first time the investigation of water molecule complexed with methylamine (CH3NH2) in solid neon was performed from 80 to 6000 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 Møller-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. [Display omitted]