The absorption spectrum of the free SiH2 radical

Abstract

The absorption spectrum of SiH2 in the visible region has been photographed at high dispersion and the rotational structure of three bands has been analyzed. In the lower electronic state 1A1 the HSiH angle is 92° 5′ and the Si–H distance 1.516 Å, while in the upper state these parameters are 123° and 1.487 Å, respectively. The observed bands correspond to excitation of the bending vibration [Formula: see text] in the upper state. In the lower state, only one excited vibrational level, 010, has been observed, yielding [Formula: see text].