X-ray diffraction (XRD) studies on (CuAlSe2)x (FeSe)1−x alloys

X-ray diffraction (XRD) studies have been performed in (CuAlSe2)x—(FeSe)1−x alloys prepared by the usual melt and anneal technique. The results showed that in the interval 0.9 > x > 0.33, a tetragonal chalcopyrite-like structure is the predominant phase (α) with traces of FeSe (β). For 0.33 > x > 0.1, α and β phases coexist, in approximately same relative amounts. Additional lines in the diffraction spectra of the new compounds CuFeAlSe3 (x = 0.5) and CuFe2AlSe4 (x = 0.33) suggest a crystallographic transition from tetragonal (I) to tetragonal (P). In our knowledge is the first time that alloys of the type (I-III-VI2)-(FeVI) have been studied in the entire composition range.