Two types of structure of lead tungstate scintillating crystals grown from
high-temperature melt of the mixed powders of PbO and WO3 have been reporte
d in the literatures. One is of space group C-4h(6)-I4(1)/a, i. e. the sche
elite structure, and the other D-4h(4)-P4/nnc. It is not easy to determine
its exact structure by the X-ray powder diffraction technique. On the bases
of measuring its Raman spectra under different geometrical configurations
and analyzing its vibration modes in the two different structures by the gr
oup theory the scheelite structure of the crystals grown from a stoichiomet
ric melt was determined in the present paper.