Theoretical Interpretation of the Zeeman Effect in the Near-Ultraviolet Bands of CS2

Abstract

Douglas and Milton have observed that the rotational lines of certain bands in the spectrum of CS₂ are broadened in a magnetic field, the broadening being proportional to the product of the magnetic field strength and the rotational quantum number. This behavior is characteristic of an orbitally nondegenerate singlet electronic state, except that the magnitude of the broadening is about 1000 times larger than usually observed. It is shown that these observations can be satisfactorily explained in terms of a model proposed by Douglas, namely, by assuming that the observed upper electronic state is the B₂ multiplet component of a (bent) ³A₂ electronic state, whose other two multiplet components, A₁ and B₁, are nearly degenerate with each other but are separated from the B₂ component.