Elastic and Piezoelectric Properties of Gd2(MoO4)3

The elastic and piezoelectric constants of Gd 2 (MoO 4 ) 3 have been measured in a temperature range from 100°C to 400°C by means of piezoelectric resonance-antiresonance method. The elastic compliance s 11 (refered to the orthorhombic axes) of the paraelectric phase can be fitted in well with a logarithmic law; however an inverse-power law holds as well in s 11 if the temperature range is limited to 40°C from the T c . In the ferroelectric phase, the elastic compliances s 11 , s 22 and the piezoelectric constants d 31 , d 32 have been analyzed on the basis of a phenomenological theory proposed by Aizu and Dvořák: the temperature dependences of these constants are well expressed by the formulae A ( T 1 - T ) -1/2 + B , being consistent with the theoretical predictions. Behavior of the spontaneous polarization is also examined.