Infra-Red and Raman Spectra of Polyatomic Molecules VI. Triborine Triamine, B3N3H6

Abstract

The Raman spectrum of liquid triborine triamine has been studied, and the infra‐red absorption of the gas measured from 2.5 to 24.5μ. The molecule is assumed to be isoelectronic with benzene, belonging to the point group D_3h, and an assignment of fundamental frequencies is given, based upon this structure. A normal coördinate treatment has been made, and used to calculate the three inactive frequencies and the isotope shifts due to the B¹⁰ isotope. The agreement between calculated and observed values is satisfactory except for the nonplanar frequencies, where strong interactions between bonds attached to the aromatic ring in metapositions are indicated. The fundamental frequencies of triborine triamine are compared with those of benzene; satisfactory correlation is obtained with the benzene frequencies given by Lord and Andrews. The frequencies of the triborine triamine are used together with structural data to calculate the thermodynamic properties of the substance.