Physical properties of single crystals of KTiPO4, KxRb1−xTiOPO4 (x = 0.85; 0.75), KGeOPO4 and KTiOAsO4

摘要: Single crystals of the title compounds optical quality and dimensions up to 30 × 25 mm were grown by flux method. During growth process formation twins consisting bicrystals was observed, even in case single-crystalline seeds. The twinning boundaries could be detected etching with hot KOH solutions. The following physical properties investigated: refractive indices, dielectric constants, thermal expansion, piezoelectric, electrooptic effects, elastic thermoelastic constants. The exhibit a quite similar behaviour. anisotropy all is quasi-tetragonal. In respect polar only small differences within mixed KxRb1–xTiOPO4 are found. Replacement P As does slightly affect properties, whereas replacement Ti Ge leads drastic reduction effects.