Rotational spectra of isotopic species of silyl fluoride. Part I: Lamb-dip measurements and quantum-chemical calculations

The Lamb-dip technique has been employed for recording the rotational spectra of three isotopic species of silyl fluoride, namely (28)SiH3F, (29)SiH3F, and (30)SiH3F, in order to improve the knowledge of their spectro- scopic parameters as well as to try to resolve their hyperfine structure. High-level quantum-chemical computations using state-of-the-art coupled-cluster techniques together with core-polarized correla- tion-consistent basis sets have been employed to provide reliable reference values for the hyperfine parameters involved and have been used to guide the experimental investigation. Analysis of the exper- imental spectra allowed to improve the accuracy of the known spectroscopic parameters as well as to determine for the first time sextic and octic centrifugal-distortion constants