Nakamura Toshikazu, Zhang Lidong, Kitou Shunsuke, Sawa Hiroshi
Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan.
Department of Applied Physics, Nagoya University, Nagoya 464-8603, Japan.
Inorg Chem. 2021 Apr 5;60(7):5206-5211. doi: 10.1021/acs.inorgchem.1c00208. Epub 2021 Mar 17.
An unusual valence one-dimensional (1D) molecular charge transfer salt (TMTTF)(NbOF) [TMTTF = tetramethyltetrathiafulvalene] with infinite anion chains was prepared. To understand the crystal structure and electronic states of the (TMTTF)(NbOF) salt, we performed synchrotron X-ray diffraction, electron spin resonance, and static magnetization measurements. There is only one independent TMTTF molecule in the unit cell of (TMTTF)(NbOF). The TMTTF cation radicals stack to form 1D columns. The effective charge of the TMTTF molecule in the crystal was estimated to be +1. The electric charge of TMTTF donors is compensated by the infinite anion chains [(NbOF)]. The magnetic susceptibility of (TMTTF)(NbOF) is 4 × 10 emu/mol at room temperature and shows weak temperature dependence above 60 K. However, some deviation appears below 60 K. The temperature dependence of the spin susceptibility shows a noticeable enhancement below 60 K. Below 5 K, the magnetization curve as a function of the magnetic field deviates from the straight line and shows a saturation tendency. The experimental results can be reproduced well with the = 2 spin system at 2 K. The detailed analysis of the crystal structure and anomalous low-temperature magnetic state magnetic properties of (TMTTF)(NbOF) are discussed.
制备了一种具有无限阴离子链的价态异常的一维（1D）分子电荷转移盐（TMTTF）（NbOF）[TMTTF = 四甲基四硫富瓦烯]。为了理解（TMTTF）（NbOF）盐的晶体结构和电子态，我们进行了同步加速器X射线衍射、电子自旋共振和静态磁化测量。在（TMTTF）（NbOF）的晶胞中只有一个独立的TMTTF分子。TMTTF阳离子自由基堆叠形成一维柱。晶体中TMTTF分子的有效电荷估计为 +1。TMTTF供体的电荷由无限阴离子链[（NbOF）]补偿。（TMTTF）（NbOF）在室温下的磁化率为4×10 emu/mol，在60 K以上显示出较弱的温度依赖性。然而，在60 K以下出现了一些偏差。自旋磁化率的温度依赖性在60 K以下显示出明显增强。在5 K以下，作为磁场函数的磁化曲线偏离直线并显示出饱和趋势。在2 K时，实验结果可以用S = 2自旋系统很好地重现。讨论了（TMTTF）（NbOF）晶体结构和异常低温磁态磁性的详细分析。
