Abstract
The frequencies of the k=0 vibrational spectra and the elastic constants of diopside have been calculated based on the modified Urey-Bradley force field. The vibrational spectra have been assigned from theoretical vibrational modes and each mode has been characterized by the contribution of force constants to potential energy. The elastic constants of diopside are grouped into three types; the first are attributable mainly to the cation polyhedra, the second to the silica chain and the third to their mixtures.
