The Room Temperature Elastic Constants of Caesium Thiocyanate

Abstract

The velocities of propagation of elastic waves in caesium thiocyanate have been measured along the three orthorhombic axes and normal to the (110), (011) and (101) planes using a double-transducer technique at 10 MHz. The velocities are found to be consistent with the orthorhombic crystal symmetry, and in favourable agreement with a recently published rigid-ion model calculation. The calculated elastic stiffness constants have values C11 = 18'9±0'7, C22 = 20·6±1·0, C33 = 28·1±1·6, C44 = 1'96±0'05, Css = 7·30±0·2, C66 = 3·04±0·07, C12 = 7'8±4'3, Cl3 = 14·8±4 and e23 = 6·3±4GPa. The calculated values for the adiabatic bulk modulus and the low temperature limiting value of the Debye temperature are 13·2 ± 3·5 GPa and 132 K respectively