Structure and Conformation of Trimethylamine

Abstract

The ground‐state rotational spectra of (CH2D) (CH3)2N, (CH3)3 15N, and (13CH3) (CH3)2N have been assigned yielding the effective moments of inertia. This information has been combined with that for (CH3)3N to give the following structural parameters: r( CN ) = 1.451 ± 0.003 Å, r( CH s ) = 1.109 ± 0.008 Å, r( CH a ) = 1.088 ± 0.008 Å, ∢ CNC = 110.9° ± 0.6°, ∢ NCH s = 111.7° ± 0.4°, ∢ NCH a = 110.1° ± 0.5°, ∢ H a CH s = 108.1° ± 0.7°, ∢ H a CH a = 108.6° ± 0.8°, where H s lies in a symmetry plane. A C 3υ equilibrium conformation has been established and the methyl groups appear to be tilted by 1.3° toward the unshared electron pair.