Radio-frequency, centimeter-wave, millimeter-wave, and infrared spectra ofSiDF3 in the v(6)=1 excited state

This paper deals with the first study of high-resolution radio-frequency, c entimeter-wave, millimeter-wave, and infrared spectra of the deuterated iso topomer of trifluorosilane, SiDF3, in its lowest degenerate excited v(6) = 1 state. Following the work of E. I. Lobodenko, O. N. Sulakshina, V. I. Per evalov, and Vl. G. Tyuterev, (J. Mol. Spectrosc. 126, 159-170 (1987)) and H arder (J. Mel. Spectrosc. 194, 145 (1999)), the data (18 A(1)-A(2) transiti ons, 229 l-type resonance transitions, 189 pure rotational transitions, and 1167 rovibrational transitions) have been fitted using three equivalent Q, D, and QD reduction schemes enabling the fit of one of the three interacti on parameters d, q(12), and epsilon, respectively, while the other two are fixed to zero. In addition to further higher order constants, either f(22)( K) or tau(K) also had to be constrained. By checking the standard deviation of each data set and the relations between parameters determined within di fferent constrains, the six reduction schemes have been shown to be unitary equivalent. Furthermore, the axial rotational ground state constant C-0 ha s been accurately determined. (C) 1999 Academic Press.