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On the Mechanism of the Spin State Transition of (Pr1-ySmy)1-xCaxCoO3

Toshiaki Fujita·Shohei Kawabata·Masatoshi Sato·Nobuyuki Kurita·Masato Hedo·Yoshiya Uwatoko
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Abstract

Transport, thermal and magnetic measurements have been carried out on (Pr1-ySmy)1-xCaxCoO3. The system exhibits a structural phase transition accompanied by the spin state change from the intermediate spin (IS) state to the low spin (LS) state with decreasing temperature T. We have constructed a T-y phase diagram for x=0.3 and T-x ones for y=0.2 and 0.3. By analyzing their magnetic susceptibilities, the number of Co ions excited to IS state (or the electron number in the eg orbitals), nIS, are roughly estimated. With increasing y or with decreasing x, nIS decreases, and the phase transition changes gradually to the (IS-LS) crossover-like one. We discuss on the possible role of the Pr atoms in realizing the transition.

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Toshiaki Fujita, Shohei Kawabata, Masatoshi Sato, Nobuyuki Kurita, Masato Hedo, Yoshiya Uwatoko. 2005-02-26. On the Mechanism of the Spin State Transition of (Pr1-ySmy)1-xCaxCoO3. https://doi.org/10.1143/jpsj.74.2294

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