A combination of Raman scattering and synchrotron X-ray powder diffraction on Group-V metal triiodides (XI(3), X = As, Sb, Bi) has revealed a continuous isostructural transition from a molecular solid to a two-dimensional layered crystal under high pressure. The loss of molecular identity proceeds by gradual pressure-induced electron transfer from intramolecular to intermolecular bonds and suppression of sp(3) hybridisation. Initial pressure increase has the effect of destroying molecular units while continued compression enhances intralayer cohesion. These two effects give rise to a non-monotonic pressure variation of the X-I bond-stretching frequency.
|Number of pages||6|
|Publication status||Published - 20 Sep 1996|
- DIAMOND-ANVIL CELL
- POWDER DIFFRACTION