Original paper

Thermal behaviour of otavite, CdCO3

Ballirano, Paolo

Abstract

The thermal behaviour of otavite, CdCO3, has been investigated from 303 K up to decomposition, which starts at 603 K and is completed, due to kinetics, at 648 K. The dependence of the cell parameters on temperature is peculiar as the a parameter slightly increases up to 453 K and subsequently contracts. Microstrain ε0follows the same behaviour. The possible occurrence of orientational disorder of the CO3group has been observed near the decomposition temperature T d. However, the partial superposition of Bragg reflections of otavite and its decomposition product, CdO, coupled to fast kinetics, lead to less accurate structural parameters near T d, requiring confirmation of such result.

Keywords

carbonaterietveld methodthermal behaviourotavitecdco3high-temperature x-ray powder diffraction