Abstract
SiD3H has been prepared by the action of lithium aluminum deuteride on SiCl3H. A parallel type absorption band has been studied with a high‐resolution infrared spectrometer. Analysis of the rotational fine structure of the band gave B0 = 1.7755±0.0008 cm—1. If the assumption is made that the structural parameters of the ground state of SiH4 are unaltered by the substitution of D for H, the Si–H internuclear distance is found to be 1.4798±0.0004 A. This is appreciably greater than 1.456 A which is accepted at present.