X-ray diffraction, Raman spectrum and magnetic susceptibility of the magnetic semiconductor Cu2FeSnS4

In an attempt to resolve the crystal structure and the corresponding space group of the magnetic semiconductor Cu2FeSnS4, samples of this compound were studied by X-ray diffraction, differential thermal analysis, Raman scattering and magnetic susceptibility. It was found that at room temperature this compound prepared by a careful crystal growth process, including annealing to equilibrium at a suitable temperature followed by slow cooling of the samples to 300 K, crystallizes in a tetragonal structure with space group P4̄.

► Cu2FeSnS4 semiconductor crystallizes in a tetragonal structure with space group P4̄.
► Order–disorder phase transition from stannite-to  -P4̄- Cu2FeSnS4 is observed at 700 °C.
► Four A-symmetry optical modes are observed from Raman spectra.
► AA-symmetry optical modes appear at 218, 284, 321 and 400 cm−1.
► P4̄- Cu2FeSnS4 behaves as an ideal Curie–Weiss antiferromagnetic material.