SYNTHESIS OF NOVEL HIGH-SPIN METAL COMPLEXES AND THEIR MULTI-FUNCTIONALITY

新型高自旋金属配合物的合成及其多功能性

• 批准号: 11640591
• 负责人: KURODA-SOWA Takayoshi
• 金额: $ 2.3万
• 依托单位: KINKI UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11640591/
• 关键词: SINGLE-MOLECULE MAGNET; Mn12 complex; MAGNETIZATION; CHARGE-TRANSFER COMPLEX; CARBOXYLIC ACID; TTF DERIVATIVES; CHARGE-TRANSFER BAND; 多核マンガン錯体; 巨大スピン; メスバウアー

The target of this project was the development of new single-molecule magnets based on Mn12 complexes.1) Chemical modification of Mn12 complexes.Mn12 complexes are known as single-molecule magnets with the highest blocking temperature. Their 16 bridging acetate groups can be replaced by other carboxylic acids. We have tried to replace the bridging acetate groups to decanoic acid, 1-adamantanecarboxylic acid, trans-3-(3-thienyl) acrylic acid, heptafluorobutanoic acid, dichloroacetic acid, and trichloroacetic acid. The ligand-exchange reactions were successful for most of ligands ; the resulting compounds retains the magnetic properties typical for single-molecule magnets. The blocking temperatures TB for them were all 2.8 K, which was a little lower than 3.0 K for the Mn12-acetate. However, the compound obtained by replacing acetate to decanoic acid showed antiferromagnetic behavior, indicating that this compound is not a single-molecule magnet.2) Formation of charge-transfer complexes of a Mn12 complex with various donor moleculesWe have tried the formation of charge-transfer complexes of a Mn12 complex with various TTF-type donor molecules. When we mixed solutions of dimethyldiphenyl-tetrathiafluvalene and Mn12-pentafluorobenzoate complex, one-electron transfer takes place to form the cationic TTF derivative and anionic Mn12 compound. By standing the methylenechloride solution with diffusion solvent for one week, reddish-black fine crystals were obtained. The solution UV-vis spectrum shows intense absorption band at around 520 nm with a molar absorption coefficient ε more than 30000, which can be attributed to the charge-transfer band between Mn12 anion and TTF-derivative cation. On the basis of solution esr, nmr and UV-vis. spectra, the formation of the charge-transfer complex occurred not immediately but rather slowly. From the magnetic susceptibility measurement, we confirmed the charge-transfer complex is a single-molecule magnet.

该项目的目标是基于MN12复合物的新单分子磁铁的开发。1）MN12复合物的化学修饰。MN12复合物被称为最高阻滞温度的单分子磁铁。他们的16个桥接醋酸群可以用其他羧酸代替。我们试图将桥接的乙酸基团替换为decan子酸，1-丙二烷二羧酸，反式3-（3-硫烯基）丙烯酸，七氟丁酸，二氯乙酸，二氯乙酸和三氯乙酸。在大多数配体中，配体交换反应都是成功的。所得化合物保留了单分子磁体的典型磁性。他们的阻塞温度为2.8 K，MN12-乙酸盐的温度低于3.0 K。然而，通过将乙酸盐替换为脱氨酸获得的化合物表现出抗磁性行为，表明该化合物不是单分子磁体。2）形成MN12复合物与各种供体分子的电荷转移复合物的形成，我们尝试了MN12 Dontorpepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepepep。当我们混合二甲基二苯基四氟韦丙烯和MN12-Pentafluorobenzoate复合物的溶液时，会发生单电子转移以形成阳离子TTF衍生物和阴离子MN12化合物。通过用扩散溶液固定甲基氯化物溶液一周，获得了红色黑色细晶体。溶液UV-VIS光谱在520 nm左右显示出巨大的损耗带，其摩尔损耗系数ε超过30000，这可以归因于MN12阴离子和TTF衍生阳离子之间的电荷转移带。基于溶液ESR，NMR和UV-VIS。光谱，电荷转移复合物的形成不是立即发生，而是慢慢发生。从磁化率测量中，我们确认电荷转移复合物是单分子磁体。