Molecular beam electric deflection of the tetrahalides CF4, CCl4, SiF4, SiCl4, GeCl4, TiF4, TiCl4, VF4, and VCl4

Abstract

Using molecular beam electric deflection, the temperature dependence of polar behavior has been studied for the molecules CF₄, CCl₄, SiF₄, SiCl₄, GeCl₄, TiF₄ TiCl₄, VF₄, VF₄, and VCl₄. A number of these molecules show polar behavior consistent with a vibrationally induced dipole moment for states with one or both of the triply degenerate vibrations excited. In four of the tetrachloride species, the presence of a vibrationally induced dipole moment was confirmed by the change in polar behavior with isotopic substituion of the Cl atoms. The deflection behavior of the transition metal tetrahalides varied from nonpolar in VCl₄ to very polar in TiF₄.