Polarized Raman and IR spectra of non-centrosymmetric PbB4O7 single crystal

Polarized Raman and IR spectra of a PbB4O7 single crystal were measured. The obtained spectra are discussed within the factor group approach for the orthorhombic P2(1)nm (C-2 nu(7)) space group with Z = 2 assuming that the crystal structure is built up of the (B4O7)(infinity)(2-) framework and Pb2+ ions. It has been shown that vibrations of borate and Pb2+ units are observed above 240 and below 160 cm(-1), respectively. The results obtained for the spontaneous Raman scattering have also been used in the discussion of the stimulated Raman spectra of the material studied - a new Raman-laser crystal. The obtained results revealed that mainly translational motions of Pb2+ ions participate efficiently in the SRS effect. Copyright (C) 2008 John Wiley & Sons, Ltd.