HIGH-PRESSURE STRUCTURAL BEHAVIOR OF SILVER(I) FLUORIDE

The high-pressure structural behaviour of AgF has been studied by the powder neutron diffraction technique. The material undergoes a pressur e-induced transition at 2.70(2) GPa from the rocksalt structure to the CsCl-type arrangement with a volume change of similar to 10%. On decr easing pressure, the reverse CsCl --> rocksalt transition occurs via a n intermediate phase possessing the hexagonal anti-NiAs structure. A p lausible structural model to explain this observation is provided, tog ether with a discussion of the relative stability of the (anti-) NiAs arrangement as a high-pressure polymorph in binary MX compounds.