Article

Electronic and magnetic properties of MnSnAs2

Nanodevice Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea
physica status solidi (b) (Impact Factor: 1.61). 05/2004; 241(7):1462 - 1465. DOI: 10.1002/pssb.200304641

ABSTRACT We have synthesized MnSnAs2 single crystals using the vertical temperature gradient solidification method. The crystal structure of MnSnAs2 is chalcopyrites, which are “genealogically” related to the more familiar tetrahedrally-coordinated zinc-blende materials, with lattice constants of a = 5.794 Å, c = 11.365 Å. Using the experimentally determined lattice constants and crystal structure, we carried out first principles electronic structure calculations, using the full-potential linearized augmented plane wave (FLAPW) method in the local density approximation (LDA). The lowest total energies were observed for the AFM state, indicating that AFM ordering in the system is energetically favored at 0 K. We find that MnSnAs2 is metallic in the electronic calculation. Interestingly, MnSnAs2 exhibited ferromagnetism with TC = 328 K. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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