Rotational spectra of isotopic species of silyl fluoride. Part II: Theoretical and semi-experimental equilibrium structure

Abstract

The equilibrium structure of silyl fluoride, SiH 3F, has been reinvestigated using both theoretical and experimental data. With respect to the former, quantum-chemical calculations at the coupled-cluster level have been employed together with extrapolation to the basis set limit, consideration of higher excitations in the cluster operator, and inclusion of core correlation as well as relativistic corrections ( r(Si–F) = 1.5911 Å, r(Si–H) = 1.4695 Å, and ∠FSiH = 108.30°). A semi-experimental equilibrium structure has been determined based on the available rotational constants for the various isotopic species of silyl fluoride ( 28SiH 3F, 28SiD 3F, 29SiH 3F, 29SiD 3F, 30SiH 3F, 30SiD 3F, 28SiH 2DF, and 28SiHD 2F) together with computed vibrational corrections to the rotational constants ( r(Si–F) = 1.59048(6) Å, r(Si–H) = 1.46948(9) Å, and ∠FSiH = 108.304(9)°).