Polymer Hybrid Materials Research Center, Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 1-1 Katahira, Aobaku, Sendai 980-8577, Japan.
Dalton Trans. 2010 Sep 21;39(35):8219-27. doi: 10.1039/c0dt00308e. Epub 2010 Aug 5.
Supramolecular cations of HOPD+([18]crown-6) and HMPD+([18]crown-6) were introduced into [Ni(dmit)2]- salts (HOPD+: o-aminoanilinium, HMPD+: m-aminoanilinium, and dmit2-: 2-thioxo-1,3-dithiole-4,5-dithiolate). Alternate layers of cations and anions were observed in the two new salts of (HOPD+)([18]crown-6)[Ni(dmit)2]- (1) and (HMPD+)([18]crown-6)[Ni(dmit)2]- (2). From X-ray crystal structural analyses, solid state 1H nuclear magnetic resonance (NMR) spectra, and dielectric constants, the thermal rotations of [18]crown-6 in both of the (HOPD+)([18]crown-6) and (HMPD+)([18]crown-6) supramolecules occurred at temperatures above approximately 200 K based on the orientational disorder in the crystal structures. The two-fold flip-flop motions of HOPD+ and HMPD+ cations in salts 1 and 2 were suppressed, due to the relatively large potential energy barriers. The [Ni(dmit)2]- anion formed pi-dimer arrangements in both salts, with a layer structure by lateral sulfur-sulfur interatomic contacts. Although the simple dimer model reproduced the magnetic properties of salt 1, the ladder arrangement of the pi-dimer in salt 2 yielded the magnetic behavior of a spin-ladder with a spin-gap of 92.5 K. The temperature dependent magnetic susceptibility of salt 2 was well reproduced by the magnetic anisotropy of J1/J2 approximately = 8 between the ladder-leg (J1: intra-dimer interaction) and ladder-rung (J2: inter-dimer interaction). The [18]crown-6 supramolecular rotator of (HMPD+)([18]crown-6) was coexistent with the spin-ladder chain of [Ni(dmit)2]- anions in salt 2.
将 HOPD+([18] 冠醚-6) 和 HMPD+([18] 冠醚-6) 的超分子阳离子引入[Ni(dmit)2]-盐中（HOPD+: o- 氨基苯胺，HMPD+: m- 氨基苯胺，dmit2-: 2-硫代-1,3-二噻唑-4,5-二硫醇）。在两种新盐（HOPD+）([18] 冠醚-6)[Ni(dmit)2]- (1) 和 (HMPD+)([18] 冠醚-6)[Ni(dmit)2]- (2) 中观察到阳离子和阴离子的交替层。通过 X 射线晶体结构分析、固态 1H 核磁共振（NMR）谱和介电常数，基于晶体结构中的取向无序，[18] 冠醚-6 在（HOPD+）([18] 冠醚-6) 和 (HMPD+)([18] 冠醚-6) 超分子中的热旋转在大约 200 K 以上的温度下发生。由于盐 1 和 2 中 HOPD+和 HMPD+阳离子的双翻翻转运动受到相对较大的势能势垒的抑制。[Ni(dmit)2]-阴离子在两种盐中形成了π-二聚体排列，通过横向硫-硫原子间接触形成层状结构。尽管简单的二聚体模型再现了盐 1 的磁性性质，但盐 2 中的π-二聚体的梯形排列产生了具有 92.5 K 能隙的自旋梯的磁行为。盐 2 的温度依赖磁化率通过 J1/J2 约为 8 的磁各向异性很好地再现，其中 J1 为阶梯腿（J1：内二聚体相互作用）之间的相互作用，J2 为阶梯梯（J2：二聚体相互作用）之间的相互作用。盐 2 中的[18] 冠醚-6 超分子旋转体与[Ni(dmit)2]-阴离子的自旋梯链共存。
