Resonant vibrational excitation of methylamine by low energy electron impact

• Published in: The Journal of chemical physics 1990-12, Vol.93 (11), p.7843-7850
• Main Authors: MOTTE-TOLLET, F, HUBIN-FRANSKIN, M.-J, COLLIN, J. E
• Format: Article
• Language: English
• Subjects: 640304 - Atomic, Molecular & Chemical Physics- Collision Phenomena; AMINES; Atomic and molecular collision processes and interactions; ATOMIC AND MOLECULAR PHYSICS; Chemistry; Chimie; COLLISIONS; ELECTRON COLLISIONS; Electron scattering; ELECTRON-MOLECULE COLLISIONS; ENERGY LEVELS; ENERGY RANGE; ENERGY-LEVEL TRANSITIONS; EV RANGE; EV RANGE 01-10; Exact sciences and technology; EXCITATION; EXCITED STATES; METHYLAMINE; MOLECULE COLLISIONS; ORGANIC COMPOUNDS; Physical, chemical, mathematical & earth Sciences; Physics; Physique, chimie, mathématiques & sciences de la terre; VIBRATIONAL STATES
• ISSN: 0021-9606; 1089-7690; 1089-7690
• DOI: 10.1063/1.459366

The study of the excitation functions of the NH2 and CH3 stretching modes of methylamine in the 4–12 eV electron impact energy range shows evidence of a broad shape resonance built on the electronic ground state and centered at 7.5 eV. This resonance is formed by the trapping of the incident electron in the second unoccupied molecular orbital and is of A″ symmetry. The elastic and inelastic angular differential cross sections measured in the 10°–90° range suggest a dominant p character. A second shape resonance located at higher energy contributes mainly to the enhancement of the CH3 deformation modes and is very likely of A′ symmetry. A comparison is made between the resonances observed in NH3 and CH3NH2. The effect of the methyl substitution is briefly discussed.