Raman study of Ba0.7Ca0.23TiO3 single crystals

In the present work we report on Raman study of Ba0.77Ca0.23TiO3 crystals in the temperature region between 12 K-300 K. We believed to gain insight on the role of Ca admixture, and search manifestations of the possible low temperature tetragonal-orthorhombic phase transition. A special attention was paid to the temperature evolution of A(1) and E components of the Gamma(15) modes. Signatures of the presence of CaTiO3 modes are evidenced at around 100 cm(-1). The Raman data give no clear indications of the soft mode driven low temperature phase transitions presence, at least down to 12 K, revealing, however increasing of disordering at cooling.