Izumiyama Naoki, Fujii Shun, Kato Kiichi, Tokunaga Ryuya, Hayami Shinya, Nakaya Manabu
Department of Material Science, Graduate School of Science, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan.
Department of Chemistry, Faculty of Science, Josai University, 1-1 Keyakidai, Sakado, Saitama 350-0295, Japan.
Dalton Trans. 2024 Jun 4;53(22):9547-9553. doi: 10.1039/d4dt00433g.
This work investigated the spin states of the cobalt(II) complexes Co() (1·X; = 4'-(4-,'-diphenylaminophenyl)-2,2':6',2''-terpyridine, X = PF, BPh) and Co() (2·X; = 4'-(4-,'-dimethylaminophenyl)-2,2':6',2''-terpyridine, X = PF, BPh) in the solid state and in solution. In the solid state, and , both containing smaller PF counter anions, showed gradual spin-crossover. In contrast, and remained in the high-spin state over the temperature range of 5-400 K due to a lower degree of molecular cooperativity. Each of the cobalt(II) complexes exhibited effects of temperature and concentration on their absorption spectra that were related to the spin states in various organic solvents. This work provides new insights into the spectroscopic properties resulting from the spin states of cobalt(II) complexes in solution.
本研究考察了钴（II）配合物Co()（1·X； = 4'-(4-,'-二苯胺基苯基)-2,2':6',2''-三联吡啶，X = PF，BPh）和Co()（2·X； = 4'-(4-,'-二甲氨基苯基)-2,2':6',2''-三联吡啶，X = PF，BPh）在固态和溶液中的自旋态。在固态下，含有较小PF抗衡阴离子的1·PF和2·PF均呈现出逐渐的自旋交叉现象。相比之下，由于分子协同性较低，1·BPh和2·BPh在5 - 400 K的温度范围内保持高自旋态。每种钴（II）配合物在各种有机溶剂中的吸收光谱都表现出与自旋态相关的温度和浓度效应。这项工作为溶液中钴（II）配合物自旋态所产生的光谱性质提供了新的见解。
