1998 Volume 7 Pages 157-159
Using the full-potential linear muffin-tin-orbital method, we study hyperfine parameters of solid iodine under high pressure theoretically. Above 15 GPa, the direction of principal component of the electric field gradient (EFG) suddenly changes as reported by Mössbauer experiments. In the monatomic phase, the large asymmetry parameter of EFG is obtained as was observed by Pasternak et al. At the molecular dissociation pressure, the change of the contact density is very small. We conclude that for the solid iodine under pressure the molecular dissociation picture which was proposed by X-ray experiments is consistent with that of the Mössbauer experiments reported by Pasternak et al.
