Iron—Selenium Fe—Se

Abstract

The phase diagram (Fig. 77) has been adopted in its main features from a publication by Schuster et al. [1], who constructed the phase boundaries from their own investigations in the region 20–66at.% Se and data published by other investigators. Two liquid miscibility gaps, two compounds, namely tetragonal β(Fe_1.04Se) and orthorhombic ε(FeSe₂), and several Fe_1−xSe (NiAs-related structures δ, δ′, γ, γ′) were observed. The Fe-rich hexagonal δphase transforms to a high temperature modification δ′ of unknown structure, and undergoes a λtransformation to the monoclinic γ′ phase.