Low-temperature thermal conductivity of ferroelastic Gd-2(MoO4)(3)

Thermal conductivity, k, of GMO crystal has been measured in temperatures f rom 0.5 to 80 K. The maximum of k appears at 18 K and its value depends on the current domain state of the sample. The ferroelastic domain walls and a ntiphase boundaries, characterised by elastic inhomogeneities, are responsi ble for additional phonon scattering and a decrease in the thermal conducti vity. The deviation of the temperature dependence of thermal conductivity f rom the classical Debye theory observed below 4 K is related to the anomalo us behaviour of specific heat in the region of the antiferromagnetic transi tion at T-N = 0.3 K. (C) 2001 Elsevier Science B.V. All rights reserved.