Refractive Indices of Pb_2MoO_5 Single Crystal

Indices of refraction of monoclinic Pb2MoO5 crystal have been measured in the visible region at room temperature. The values obtained at 589.3 mμ are nX=2.1833±0.0005, nY=2.1967±0.0005, nZ=2.3188±0.0006, and (+)2V=38.2±1.4°. Dispersion characteristics of the refractive indices are well explained by the two-oscillator model. An oscillator corresponding to ~190 mμ, which is considered to be an average of several transitions, is the major contributor to the dispersion characteristics; another one observed at 336 mμ, the absorption edge, plays a less important role. Wavelength dependence of the optic-axis angle and the angle between the optic elasticity axis X and the perfect cleavage plane (20 1¯) are also given.