Konarev Dmitri V, Khasanov Salavat S, Otsuka Akihiro, Saito Gunzi, Lyubovskaya Rimma N
Division of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. konarev@ icp.ac.ru
Inorg Chem. 2007 Mar 19;46(6):2261-71. doi: 10.1021/ic0611138. Epub 2007 Feb 22.
A series of ionic multicomponent complexes comprising C60 and C70 anions and coordinating assemblies of methyldiazabicyclooctane cations with metal tetraphenylporphyrins, (MDABCO+)2.MIITPP.(C60(70)-)2.Sol. (C60, M = Zn (1); C60, M = Co (2); C60, M = Mn (3); C60, M = Fe (4); C70, M = Mn (5); and C70, M = Fe (6)) has been obtained. IR- and UV-vis-NIR spectra of 1-6 justified the formation of C60*- in 1-4 and single-bonded (C70-)2 dimers in 5 and 6. Co and Mn atoms are six-coordinated in the (MDABCO+)2.MIITPP units with relatively long M-N bonds of 2.475(2), 2.553(2), and 2.511(3) A for 2, 3, and 5, respectively. Isostructural complexes 2 and 3 contain C60*- zigzag chains separated by the (MDABCO+)2.MIITPP units, whereas in 5 the layers formed by the (C70-)2 dimers alternate with those composed of the (MDABCO+)2.MnIITPP units and noncoordinating MDABCO+ cations. Negative Weiss constants of -13 (1), -2 (3), and -2 (4) K indicate the antiferromagnetic interaction of spins, which decreases the magnetic moment of the complexes below 70-120 K. The EPR signals of 1 and 4 attributed to C60*- are split into two components at the same temperatures, which broaden and shift to higher and lower magnetic fields with the temperature decrease. Complexes 2 and 3 show single EPR signals with g-factors equal to 2.1082 and approximately 2.4 at 293 K, respectively. These values are mean between those characteristic of MIITPP and C60*-, and, consequently, the signals appear due to exchange coupling between these paramagnetic species. The antiferromagnetic ordering of C60*- spins below 70-100 K shifts g-factor values closer to those characteristic of individual MIITPP (g = 2.1907 (2) and approximately 4.9 (3) at 4 K). In contrast to 1-4, complex 5 shows paramagnetic behavior with Weiss constant close to 0.
已获得一系列离子多组分配合物，其包含C60和C70阴离子以及甲基二氮杂双环辛烷阳离子与金属四苯基卟啉的配位组装体，(MDABCO+)2.MIITPP.(C60(70)-)2.Sol.（C60，M = Zn (1)；C60，M = Co (2)；C60，M = Mn (3)；C60，M = Fe (4)；C70，M = Mn (5)；以及C70，M = Fe (6)）。1 - 6的红外光谱和紫外 - 可见 - 近红外光谱证明在1 - 4中形成了C60* - ，在5和6中形成了单键合的(C70-)2二聚体。在(MDABCO+)2.MIITPP单元中，Co和Mn原子为六配位，对于2、3和5，其M - N键相对较长，分别为2.475(2)、2.553(2)和2.511(3) Å。同构配合物2和3包含由(MDABCO+)2.MIITPP单元隔开的C60* - 之字形链，而在5中，由(C70-)2二聚体形成的层与由(MDABCO+)2.MnIITPP单元和非配位的MDABCO+阳离子组成的层交替排列。 - 13 (1)、 - 2 (3)和 - 2 (4) K的负魏斯常数表明自旋的反铁磁相互作用，这使得配合物的磁矩在70 - 120 K以下降低。归因于C60* - 的1和4的电子顺磁共振信号在相同温度下分裂为两个分量，随着温度降低，它们变宽并向更高和更低磁场移动。配合物2和3在293 K时分别显示g因子等于2.1082和约2.4的单电子顺磁共振信号。这些值介于MIITPP和C60* - 的特征值之间，因此，这些信号是由于这些顺磁物种之间的交换耦合而出现的。低于70 - 100 K时C60* - 自旋的反铁磁有序使g因子值更接近单个MIITPP的特征值（4 K时g = 2.1907 (2)和约4.9 (3)）。与1 - 4相反，配合物5表现出顺磁行为，魏斯常数接近0。
