Materials Research Bulletin, Vol.31, No.8, 1001-1005, 1996
Optical-Absorption Properties of Pb5Geo4(Vo4)(2) Single-Crystals
Thermal and pulling conditions have been optimized in a laboratory Czochralski apparatus to yield optically homogeneous crystals of hexagonal Pb5GeO4(VO4)(2). The wavelength dependence of absorption coefficient was calculated from transmission and reflection measurements in the visible region. A hypothesis regarding the zone structure in connection to the fundamental absorption edge was raised and the bandgap width corresponding to indirect transition at room temperature was determined from the alpha(1/2)-hv curve.
Keywords:PB5(GEO4)(VO4)2