Elastic and Piezoelectric Coefficients of Single-Crystal Barium Titanate

Mechanical resonance and antiresonance frequencies were measured on barium titanate single-crystal elements maintained under electric dc bias from -50\ifmmode^\circ\else\textdegree\fi{}C to +150\ifmmode^\circ\else\textdegree\fi{}C. A complete set of elastic, piezoelectric, and dielectric constants of the tetragonal modification at 25\ifmmode^\circ\else\textdegree\fi{}C is obtained. The elastic compliances show substantial deviation from cubic symmetry. Measurements in the orthorhombic state show longitudinal compliance four times higher than in the tetragonal state.