RAMAN SCATTERING IN NON-STOICHIOMETRIC LITHIUM NIOBATE CRYSTALS WITH A LOW PHOTOREFRACTIVE EFFECT

Raman spectra of lithium niobate single crystals strongly doped by zinc and BUTTON DOWNS magnesium, it has been established, contain low-intense bands with frequencies 209, 230, 298, 694, and 880 cm−1.Ab ignition calculations fail to attribute these bands to fundamental vibrations of A2 symmetry type unambiguously.Such vibrations are prohibit

The West Coast of Pillows South Africa between St Helena Bay to the north and Langebaan Lagoon to the south is characterised by numerous granite protrusions.These outcrops are elements of the underlying Cape Granite Suite, which forms the bedrock of a large part of the Western Cape.Granite contains high levels of natural radionuclides, which result