Effect of Nonmagnetic Substitution on the Magnetic Properties and Charge-Transfer Phase Transition of an Iron Mixed-Valence Complex, (n-C3H7)4N[FeIIFeIII(dto)3] (dto = C2O2S2)
Effect of Nonmagnetic Substitution on the Magnetic Properties and Charge-Transfer Phase Transition of an Iron Mixed-Valence Complex, (n-C3H7)4N[FeIIFeIII(dto)3] (dto = C2O2S2)
复制标题
非磁性取代对铁混合价配合物 (n-C3H7)4N[FeIIFeIII(dto)3] (dto = C2O2S2) 磁性和电荷转移相变的影响
DOI：
10.1021/ic3010954
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发表时间：
2012
影响因子：
4.6
通讯作者：
Hiromichi Ida
中科院分区：
文献类型：
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作者：
Y. Mizuno;M. Okubo;K. Kagesawa;D. Asakura;T. Kudo;H.S. Zhou;K. Oh-ishi;A. Okazawa;N. Kojima;Hiromichi Ida
铁的混合价配合物（n-C3 H7）4 N [FeIIFeIII（dto）3]除了在TC = 7 K时发生铁磁相变外，还在120 K时发生了FeII和FeIII之间可逆的热诱导电子转移，这就是所谓的电荷转移相变（CTPT）.为了研究CTPT的机理，我们合成了一系列磁稀释配合物（n-C3 H7）4 N [FeII 1-xZnIIxFeIII（dto）3]（dto = C2 O2 S2;x= 0-1），并进行了磁化率、介电常数和57 Fe-Mo穆斯堡尔谱的测量。随着ZnII浓度（x）的增加，CTPT逐渐受到抑制，在x = 0.13时消失.另一方面，铁磁转变温度（TC）最初从7 K提高到12 K betweenx= 0.00和0.05，尽管ZnII离子的结晶性，然后它单调下降从12 K到3 K随着ZnII浓度的增加。这种异常的依赖性ofTCon ZnII浓度是有关的铁磁状态的自旋配置的变化所造成的部分抑制的CTPT。
The iron mixed-valence complex (n-C3H7)4N[FeIIFeIII(dto)3] exhibits a novel type of phase transition called charge-transfer phase transition (CTPT), where the thermally induced electron transfer between FeIIand FeIIIoccurs reversibly at ∼120 K, in addition to the ferromagnetic phase transition atTC= 7 K. To investigate the mechanism of the CTPT, we have synthesized a series of magnetically diluted complexes (n-C3H7)4N[FeII1–xZnIIxFeIII(dto)3] (dto = C2O2S2;x= 0–1), and carried out magnetic susceptibility and dielectric constant measurements and57Fe Mössbauer spectroscopy. With increasing ZnIIconcentration (x), the CTPT is gradually suppressed and disappears atx≈ 0.13. On the other hand, the ferromagnetic transition temperature (TC) is initially enhanced from 7 K to 12 K betweenx= 0.00 and 0.05, despite the nonmagnetic nature of ZnIIions, and then it decreases monotonically from 12 K to 3 K with increasing ZnIIconcentration. This anomalous dependence ofTCon ZnIIconcentration is related to a change in the spin configuration of the ferromagnetic state caused by the partial suppression of the CTPT.