Specific features in the thermal conductivity of synthetic opals

Data on the thermal conductivity ϰ ph of the cluster lattice of synthetic opals are analyzed. All opals are divided into two groups according to the temperature dependence of their ϰ ph . These are opals-1, whose thermal conductivity behaves like ϰ ph ( T ) of quasi-crystalline materials, and opals-2, with a ϰ ph ( T ) dependence typical of classical amorphous solids. Possible reasons for this difference are considered. An attempt is made to explain the complex temperature hysteresis in ϰ ph ( T ) observed earlier in opals-2.