Anisotropic susceptibility of La2- xSrxCoO4 related to the spin states of cobalt

  title={Anisotropic susceptibility of La2- xSrxCoO4 related to the spin states of cobalt},
  author={Nils Hollmann and Maurits W. Haverkort and Matthias Cwik and M. Benomar and M. Reuther and Arata Tanaka and Thomas Lorenz},
  journal={New Journal of Physics},
We present a study of the magnetic susceptibility of La2- xSrxCoO4 single crystals in a doping range 0.3 ⩽ x ⩽ 0.8. Our data show a pronounced magnetic anisotropy for all compounds. This anisotropy is in agreement with a low-spin ground state (S = 0) of Co3+ for x ⩾ 0.4 and a high-spin ground state (S = 3/2) of Co2+. We compare our data with a crystal-field model calculation assuming local moments and find a good description of the magnetic behavior for x ⩾ 0.5. This includes the pronounced… 

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