Magnetic and transport properties of Co_1±δCr_2∓δSe₄

Single crystals of ${Co}_{1\pm \delta }{Cr}_{2\mp \delta }{Se}_4$ were grown using chemical vapor method with CrCl₃ as a transporting agent. Magnetic measurements on the ${Co}_{1\pm \delta }{Cr}_{2\mp \delta }{Se}_4$ crystals confirm an antiferromagnetic ordering below the Neel temperature of T _N = 230 K. Neutron diffraction studies performed on the ${Co}_{1\pm \delta }{Cr}_{2\mp \delta }{Se}_4$ powder show that the long-range antiferromagnetic ordering is accompanied by a doubling of the c crystallographic axe. For the ${Co}_{1\pm \delta }{Cr}_{2\mp \delta }{Se}_4$ single crystals electrical resistivity displays an anisotropic behavior: resistivitiy within the (100) plane increases till T _N and then decreases as temperature increases. Resistivity in the orthogonal direction increases with temperature with a change in the slope above T _N. Muon spin relaxation experiments on the ${Co}_{1\pm \delta }{Cr}_{2\mp \delta }{Se}_4$ crystals confirm both the long-range magnetic order and ordering temperature established by other techniques. (paper)