Abstract
Cell parameters of four natural orthopyroxenes were measured by X-ray powder method at high temperature.
The linear thermal expansion coefficients were calculated from their temperature derivatives. The present values are different significantly from those of a previous work.
Possibly, there is a positive correlation between linear thermal expansion coefficients and linear compressibilities for isotropic solids with the same crystal structure. This correlation holds also for each crystallographic axis of the present orthopyroxenes and the other anisotropic materials with a few exceptions.
