Preparation and pressure-induced semiconductor-metal transition of CrSi2 nanocrystals

Semiconducting chromium disilicide (CrSi2) nanocrystals were prepared by th e are plasma method, and characterized by X-ray diffraction and transmissio n electron microscopy. The pressure-induced semiconductor-metal transition in CrSi2 nanocrystals was investigated in a diamond anvil cell by electrica l resistance measurements at high pressure. The pressure dependence of resi stance at room temperature in the pressure range of 0-10 GPa revealed an ex ponential decrease up to 3.2 GPa, indicating a linear closing of the energy gap, followed by an almost pressure-independent metallic regime. This phas e transition is discussed in terms of previous band structure calculations. (C) 1999 Elsevier Science B.V. All rights reserved.