THE RAMAN SPECTRUM OF CRYSTALLINE LITHIUM NITRATE

$^{1}$ W. Bues, Z. physik, Chem. Neue Folge 10, 1 (1957). $^{2}$ D.L. Rousseau, R.E. Miller and G.E. Leroi, J. Chem. Phys. (in press).Author Institution: Department of Chemistry, Michigan State UniversityRaman scattering from an oriented single crystal of anhydrous lithium nitrate at room temperature has been observed under various conditions of polarization. The sample was illuminated by He-Ne and Ar-ion laser sources, and the scattered light measured photoelectrically after dispersion by a double monochromator. Careful depolarization measurements were made on the Ramanactive internal vibrations $[\nu_{1}(A_{1g})=1071.0, \nu_{3}(E_{g})=1384.6, \nu_{4}(E_{g})=735.4, 2\nu_{2}(A_{1g})=1675.1 cm^{-1}]$, and the previously unreported lattice modes $[L_{6}(E_{g})=124.4, L_{7}(E_{g})=237.2 cm^{-1}]$. The instrumentation utilized for this study, the assignment of the lattice modes and the effects of birefringence will be discussed, and the results compared to previous investigations of $LiNO_{2}$ (ref. $^{1}$) and $NaNO_{3}$ (ref. $^{2}$)