A CREATION OF A STRONGLY-CORELATED SPIN-CHARGE-LATTICE COUPLED METAL-COMPLEX SYSTEM

我们研究了具有自旋-电荷-晶格动力学耦合的一维金属-二聚体体系，该体系表现出多种与金属-绝缘体跃迁相关的电荷有序态。本文研究了一个存在一维三键-I-M-M-I-三键链的MMX-链体系。MMX链的一些可能的1-D结构模式如下所示。（1）[三键] M ^&lt;2.5 +&gt;-M ^&lt;2.5 +&gt;-X-M ^&lt;2.5 +&gt;-X-M ^&lt;2.5 +&gt;-M ^&lt;2.5 +&gt;-X [三键]（2）[三键] M ^&lt;2 +&gt;-M ^-X-M ^&lt;3 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;2 +&gt;-M ^&lt;2 +&gt;-X-M ^&lt;3 +&gt;-M ^&lt;3 +&gt;-X [三键]（3）[三键] M ^&lt;2 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;2 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;2 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;2 +&gt;-M ^&lt;3 +&gt;-X [三键]（4）[三键] M ^&lt;2 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;3 +&gt;-M ^&lt;2 +&gt;-X-M ^&lt;3 +&gt; <2->2 +&gt;-M ^&lt;3 +&gt;-X-M ^&lt;3 +&gt;-M ^&lt;2 +&gt;-X [三键]根据我们最近的工作，我们发现Ni_2（MeCS_2）_4I盐具有场致相变，并伴随着一维Heisenberg AF磁自旋系统（J =-50 K（α-相）和居里自旋系统（J =-0.50 K）之间的自旋跃迁 关于我们 K（b相）。为了研究Ni_2（MeCS_2）_4I的两种不同的自旋态，我们对它进行了物理测量，发现它在180 - 370 K的温度范围内表现出半导体性质，这与Mott-Hubbard绝缘体相一致。XPS谱图显示了+II和+III的捕获价态。通过拉曼光谱、红外光谱、紫外-可见-近红外光谱和磁化率的测定，证明了各相具有-I-Ni ^&lt;2 +&gt;-Ni ^&lt;3 +&gt;-I-Ni ^&lt;2 +&gt;-I-Ni ^&lt;2.5 +&gt;-Ni ^&lt;2.5 +&gt;-I-的一维结构模式。其甚至在室温和零场下也可以作为亚稳态获得。另一方面，如果在300 K下施加5T的磁场，则b相可逆地转变为a相。这种场诱导现象被认为是来自轨道自由度，导致场诱导轨道有序。详细调查正在进行中。少

We have focused on a one-dimensional metal-dimer system with dynamical spin-charge-lattice coupling, exhibiting many kinds of charge-ordered states associated with metal-insulator transitions. In this report, we present on an MMX-chain system in which there exists 1-D 【triple bond】-I-M-M-I-【triple bond】 chains. Some of the possible 1-D structural modes for the MMX chain are shown below.(1)【triple bond】M^<2.5+>-M^<2.5+>-X-M^<2.5+>-M^<2.5+>-X-M^<2.5+>-M^<2.5+>-X【triple bond】(2)【triple bond】M^<2+>-M^<2->-X-M^<3+>-M^<3+>-X-M^<2+>-M^<2+>-X-M^<3+>-M^<3+>-X【triple bond】(3)【triple bond】M^<2+>-M^<3+>-X-M^<2+>-M^<3+>-X-M^<2+>-M^<3+>-X-M^<2+>-M^<3+>-X【triple bond】(4)【triple bond】M^<2+>-M^<3+>-X-M^<3+>-M^<2+>-X-M^<2+>-M^<3+>-X-M^<3+>-M^<2+>-X【triple bond】According to our recent work, the Ni_2(MeCS_2)_4I salt was found to exhibit a field-induced phase transition accompanying a spin transition between a 1-D Heisenberg AF magnetic spin system with J 〜 -50 K (a-phase) and Curie spin system with J 〜 0 … More K (b-phase). In order to investigate two different spin state, several physical measurements were carried out on Ni_2(MeCS_2)_4I.It exhibits a semiconducting behavior in the temperature range of 180 - 370 K, which is consistent with a Mott-Hubbard insulator. The XPS spectra shows a trapped-valence state of +II and +III. Each phase is considered to have the 1-D structural mode of -I-Ni^<2+>-Ni^<3+>-I-Ni^<3+>-Ni^<2+>-I-Ni^<2.5+>-Ni^<2.5+>-I-, which was confirmed by Raman, IR, UV-VIS-NIR spectra and magnetic susceptibility.At 2 K, if the magnetic field of 5 T is applied, the a-phase is transformed to the b-phase, which can be obtained as a metastable state even at room temperature and zero-field. On the other hand, if the magnetic field of 5 T is applied at 300 K, the b-phase is reversibly transformed to the a-phase. This field-induced phenomenon is considered to be derived from an orbital degree of freedom, resulting the field-induced orbital ordering. Detailed investigations are in progress. Less