A Hofmann-type two-step spin-crossover (SCO) complex with a pyrimidine derivative ligand, Fe(4-methylpyrimidine)₂[Au(CN)₂]₂, was synthesized, and this complex shows a two-step SCO phenomenon in the intermediate state. Symmetry breaking also occurs in the intermediate state. These results reveal three spin states within the complex for high-spin (HS), HS_0.5LS_0.5, and low-spin (LS).

中文翻译：

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在霍夫曼型配位化合物{Fe（4-甲基嘧啶）2 [Au（CN）2] 2}中的新型两步Fe-Au型自旋交叉行为。

合成了具有嘧啶衍生物配体Fe（4-甲基嘧啶）₂ [Au（CN）₂ ] ₂的霍夫曼型两步自旋交联（SCO）络合物，该络合物在反应中显示出两步SCO现象。中间状态。对称破坏也发生在中间状态。这些结果揭示了复合物中高旋转（HS），HS _0.5 LS _0.5和低旋转（LS）的三种自旋状态。