Structural transformation from amorphous to hexagonal tungsten bronze FeF3, studied by Mössabauer spectroscopy

Abstract By annealing vapor-deposited amorphous FeF 3 at 180°C for 2 days, a crystalline phase has been obtained; it was identified by Mossbauer spectroscopy as hexagonal tungsten bronze FeF 3 . the structural quality of this phase was good enough to provide the hyperfine parameters and notably the electric field gradient tensor. The role of Fe 2+ impurities in this new synthesis method is discussed.