Magnetic Properties of 1,3,5-Tris[bis(<i>p</i>-methoxyphenyl)amino]benzene Cation Radicals
作者:Kazunari Yoshizawa、Masashi Hatanaka、Hiroki Ago、Kazuyoshi Tanaka、Tokio Yamabe
DOI:10.1246/bcsj.69.1417
日期:1996.5
In order to pursue the possibility of charge-transfer organic ferromagnets, magnetic properties of the monocationic ClO4- and BF4-salts of a triaminobenzene derivative, 1,3,5-tris[bis(p-methoxyphenyl)amino]benzene (TBMAB), were characterized by means of ESR and a Faraday-type magnetic balance. MNDO-PM3 calculations predicted 1,3,5-tris(diphenylamino)benzene (TDAB) dication and trication to be ground-state triplet and quartet, respectively. Thus these triaminobenzenes fulfill the necessary precondition for the appearance of intermolecular ferromagnetic coupling based on so-called McConnell’s second model. Negative Weiss constants (−1 to 0 K) and low spin concentrations (7—8 %) were observed for TBMAB–ClO4 and TBMAB–BF4, although, according to this rule, intermolecular ferromagnetic coupling is expected to occur for these systems.
为了探索电荷转移有机铁磁体的可能性,我们通过 ESR 和法拉第式磁天平对三氨基苯衍生物 1,3,5-三[双(对甲氧基苯基)氨基]苯 (TBMAB) 的单配位 ClO4 盐和 BF4 盐的磁性能进行了表征。根据 MNDO-PM3 计算,1,3,5-三(二苯基氨基)苯(TDAB)的二阳离子和三阳离子分别为基态三重和四重。因此,根据所谓的麦康奈尔第二模型,这些三氨基苯符合出现分子间铁磁耦合的必要前提条件。在 TBMAB-ClO4 和 TBMAB-BF4 中观察到了负韦斯常数(-1 至 0 K)和低自旋浓度(7-8 %),尽管根据这一规则,分子间铁磁耦合有望在这些体系中出现。