The Infra-Red Spectrum of Methylamine

Abstract

The infra‐red spectrum of methylamine has been measured over the range 7000–12,000A using low dispersion, and a vibrational assignment has been made to the bands observed. The rotational structure of a band at 9950A previously reported has been examined under higher dispersion. The band is of the perpendicular type and an analysis leads to values of the molecular structural constants in agreement with those to be expected on other grounds, namely r_CN∼1.47A, r_NH∼1.02A, C–N̂–H 108°, and a tetrahedral methyl group. There is no evidence for the occurrence of internal rotation in the methylamine molecule.