Mössbauer study of Fe1 − xBx amorphous alloys: A model of the atomic structure

Fe1 − xBx (0.12 ⩽ x ⩽ 0.25) glasses have been studied by Mössbauer spectroscopy. The hyperfine field distributions show that the structure of boron rich glasses (x ⩾ 0.20) may be described as a packing of iron trigonal prisms centered by boron atoms. Below x = 0.20, a description with a mixture of such environments and of iron sites without boron neighbours is appropriate. A model grounded on the structural operations which generate the crystalline counterparts from close packed structures is then proposed. The decomposition of the structure in two kinds of environments follows from this model and the corresponding critical concentrations are discussed.