Evidence for a temperature-induced spin-state transition of Co3+ in La2−xSrxCoO4
نویسندگان
چکیده
We study the magnetic susceptibility of mixed-valent La2−xSrxCoO4 single crystals in the doping range of 0.5 x 0.8 for temperatures up to 1000 K. The magnetism below room temperature is described by paramagnetic Co2+ in the high-spin state and by Co3+ in the nonmagnetic low-spin state. At high temperatures, an increase in susceptibility is seen, which we attribute to a temperature-induced spin-state transition of Co3+. The susceptibility is analyzed by comparison to full-multiplet calculations for the thermal population of the highand intermediate-spin states of Co3+.
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