ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Thermal Expansion of Spinels MgCr₂0₄, MgAl₂0₄ and MgFe₂0₄

I. Kaprálik

Institute of Inorganic Chemistry, Slovak Academy of Sciences, Bratislava 9

Abstract:  The lattice constants of the cubic spinels MgCr₂O₄, MgAl₂Cl₂ and MgFe₂O₄ have been measured by high-temperature powder X-ray diffraction method in the temperature range from 20 to 1300°C. The dependence of the lattice constants on the temperature has been expressed by polynoms of second order, the respective coefficients being found by the least-squares method. The coefficients of the true thermal expansion α = a₁± a₂t have been determined. The expansion of the above spinels are reversible. The thermal expansion of MgFe₂O₄ includes a contribution Aast which is a function of the degree of inversion.

Full paper in Portable Document Format: 239a665.pdf

Chemical Papers 23 (9) 665–670 (1969)