Fourier transform microwave spectroscopy of the SiCl+ ion

Abstract

Fourier transform microwave spectra for the J=1 <- 0 and 2 <- 1 rotational transitions of the SiCl+ ion were observed for two isotopologues (Cl-35 and Cl-37) in the ground and the first excited vibrational states of the ground (1)Sigma(+) electronic state. Thanks to the high resolution of the FTMW spectrometer, hyperfine structures due to the quadrupole moment of the chlorine nucleus and the nuclear spin-rotation interaction were fully resolved. The observed FTMW spectra were combined with previously reported MMW and diode laser spectra in an analysis to determine the mass-independent Dunham coefficients U-k,U-l as well as a mass scaling parameter Delta(Cl)(01) = -0.856(30). The equilibrium bond length of SiCl+ determined is r(e) = 1.9439729(10) angstrom and the nuclear quadrupole coupling constant of (SiCl+)-Cl-35 is eQq(e) = -11.8788(23) MHz. (C) 2017 Elsevier Inc. All rights reserved.