Band structure, magnetic, and transport properties of two dimensional compounds Sr2-xGdxCoO4

The layered perovskite compound Sr2-xGdxCoO 4 has not yet been subjected to detailed study so far. In this report, structures, transport, magnetic properties, and first principle calculations will be reported for the two dimensional compounds Sr 2-xGdxCoO4 (x 0.5, 0.75, 1, 1.25). Rietveld refinement revealed that these compounds are crystallized in K2NiF 4-type structures with space group I4/mmm. It was found that the lattice parameter c decreases as x increases. Through the Curies Weiss fitting of the temperature dependent magnetization, it was found that the Sr 1.25Gd0.75CoO4 sample exhibits a weak ferromagnetic to paramagnetic transition at about 62 K, with a Curie constant of 0.113 emu K/mol. Band structure calculations indicated that electrons of these compounds are spin polarized at the Fermi level. The 2-D Variable Range Hopping model fitting indicated that the two dimensional variable range hopping mechanism could be used to account for the conducting mechanism for these samples. 2013 American Institute of Physics.