The Zeeman Effect andΛ-Type and Spin Doubling in the CaH Bands

Abstract

A more detailed discussion of the Zeeman effect in the 6389A ${}_{}{}^2{}_{}{}^{}\Sigma$, ${}_{}{}^2{}_{}{}^{}\Sigma$ band of CaH than that given previously with W. Bender is presented. General agreement with the assumption that the magnetic energy in a ${}_{}{}^2{}_{}{}^{}\Sigma$ state is largely due to the interaction of the electron spin and the external field is obtained for band lines of low $K$ value, but marked differences and asymmetries in the patterns occur for lines from the higher rotational levels. The neglected coupling between the component $\rho$ of $L$ along the rotational axis of the molecule and the field will account completely for these deviations, and these observations together with those on the Zeeman effect of the lines of these higher rotational levels in the ${}_{}{}^2{}_{}{}^{}\Pi$, ${}_{}{}^2{}_{}{}^{}\Sigma$ band of CaH are shown to be in accord with the explanation by Van Vleck and Mulliken and Christy of the large $\Lambda$-type and spin doubling in these states.