Abstract
Inter- and intramolecular distances in tellurium have been investigated at pressure up to 20 GPa by the Rietveld analysis. Previously reported phase transitions from Te-I to Te-II, from Te-II to Te-III, and from Te-III to Te-IV are observed at 4 GPa, 7 GPa, and 11 GPa, respectively. In the Te-II and Te-III phases, with increasing pressure, not only four intealayer bond lengths but also one interlayer distance approach continuously to the same bond length, 3A, which is equal to the interatomic distance in the next Te-IV phase. This suggests that bonding character changes continuously from covalent character to metallic one with pressure.
