X-ray absorption study of nickel doping on electronic properties of ZnCr2Se4

We present temperature dependant studies of Cr K, Ni K and Se K absorption edges of ZnCr1.8Ni0.2Se4 and NiCr2Se4. The EXAFS and XANES analysis is consistent with nickel located on the octahedral site. The experiment is compared with the results of the FPLO-CPA numerical calculations and the angular momentum projected densities of states. The calculations reveal that both nickel (0.5 mu(B)) and selenium (0.1 mu(B)) possess magnetic moment and are polarised opposite to chromium (3.1 mu(B)). Calculation results imply contribution from Se 4p electrons to the magnetism and Cr/Ni 4s to charge balance of the system. (C) 2011 Elsevier Ltd. All rights reserved.