Microwave Rotational Spectrum of Indium Monochloride

Abstract

With a high-temperature Stark-spectrometer the J=4←3 rotational spectrum of 115In35Cl has been observed. Quadrupole hyperfine structure has been observed for the lowest four vibrational states. In an analysis of the spectrum the following constants have been derived: the rotational—vibrational constants Y01, Be, Y11(≈—αe), Y21(≈γe), Y02(≈—De), and Y20(≈—ωexe); the quadrupole coupling constants eqQ including the dependence on the vibrational state; the coefficients a0, a1, and a2 of the internuclear potential; and the internuclear distance re. From the quadrupole hyperfine structure it is concluded that the molecule is 77% ionic, and that the antishielding factor of In+—γ∞≈65.