Crystal growth, thermal expansion, pyroelectricity and vibrational spectroscopy of barium antimony tartrate, Ba[Sb2((+)C4H2O6)(2)] . 3H2O
Abstrakt
The tetragonal polar barium antimony tartrate trihydrate, Ba[Sb2((+)C4H2O6)(2)] . 3H2O, was grown to large single crystals of optical quality and several cm dimensions. A vibrational spectroscopy study, thermal expansion measurements and a determination of the pyroelectric properties were performed and possibilities for phase matching for second harmonic generation (SHG) were analysed.
The crystals show a remarkable high pyroelectric coefficient, a moderate anisotropy of thermal expansion and allow for type I and type II phase matching for collinear SHG. A redetermination of the crystal structure of Ba[Sb2((+)C4H2O6)(2)] . 3H2O at 150 K is given in addition, together with the vibrational spectra and crystal structures of two new related compounds, Ba[As2((+)C4H2O6)(2)] . 3H2O and Ba[Sb2((+)C4H2O6)(2)] . 4H2O, determined at the same temperature.