Supramolecular Approach to the Synthesis of [60]Fullerene−Metal Dithiocarbamate Complexes, {(M^II(R₂dtc)₂)_<i>x</i>·L}·C₆₀ (M = Zn, Cd, Hg, Fe, and Mn; <i>x</i> = 1 and 2). The Study of Magnetic Properties and Photoconductivity

Coordination assemblies formed by metal(II) dithiocarbamates MII(R2dtc)2 (M = Zn, Cd, Hg, Mn, and Fe; R = Me, Et, iPr, nPr, and nBu) and nitrogen-containing ligands (L = DABCO, DMP, and HMTA) are shown to be sterically well consistent with the spherical shape of fullerenes and are effectively cocrystallized with them to form complexes {(MII(R2dtc)2)x·L}·C60 (x = 1 and 2) with layered or three-dimensional (3D) packing of fullerene molecules (1−11). For the first time the molecular structures of the MII(R2dtc)2 assemblies in the complexes with C60 are presented (including those with M = Mn, Fe, and Hg). According to optical and electron paramagnetic resonance (EPR) spectroscopy 1−11 have a neutral ground state. Magnetic susceptibilities of {[MII(Et2dtc)2]2·DABCO}·C60·(DABCO)2 (M = Mn and Fe) follow the Curie–Weiss law in the 50–300 K range with the Weiss constants Θ = 0.35 and 1.70 K, respectively. Magnetic moments of the complexes equal to 8.23 and 6.88 μB at 300 K correspond to the high-spin state of the MnII (S = 5/2) and FeII (S = 2) ions. The increase of μeff observed below 35 and 50 K up to 8.5 μB (at 3 K) and 7.4 μB (at 6 K) indicates the manifestation of short-range ferromagnetic interactions between MII spins in the isolated [MII(Et2dtc)2]2·DABCO dimers. Under illumination by white light, the complexes show up to 102 times increase of photocurrent. The main contribution to the generation of free charge carriers is provided by direct charge transfer from {MII(R2dtc)2}2·L to C60. It was found that photocurrent increases in magnetic field with induction B < 1 T.由二硫代氨基甲酸盐金属(II)配合物MⅡ(R₂dtc)₂（其中M为Zn、Cd、Hg、Mn及Fe；R为Me、Et、iPr、nPr及nBu）与含氮配体（L=DABCO、DMP、HMTA）构建的配位组装体，在空间构型上与富勒烯的球形结构高度匹配，可与富勒烯高效共结晶，形成{(MⅡ(R₂dtc)₂)ₓ·L}·C₆₀（x=1和2）类配合物，该类配合物的富勒烯分子呈现层状或三维（3D）堆积结构（1−11）。 本研究首次报道了这类与C₆₀共结晶的MⅡ(R₂dtc)₂组装体的分子结构（包括M为Mn、Fe及Hg的体系）。通过光学及电子顺磁共振（Electron Paramagnetic Resonance，EPR）光谱表征可知，配合物1−11均呈中性基态。 对于{[MⅡ(Et₂dtc)₂]₂·DABCO}·C₆₀·(DABCO)₂（M为Mn和Fe），其磁化率在50–300 K范围内符合居里-外斯定律，对应的外斯常数Θ分别为0.35 K和1.70 K。该类配合物在300 K时的磁矩分别为8.23 μB和6.88 μB，对应MnⅡ（自旋量子数S=5/2）与FeⅡ（S=2）离子的高自旋态。 在35 K和50 K以下，有效磁矩μeff分别升至8.5 μB（3 K时）与7.4 μB（6 K时），这表明孤立的[MⅡ(Et₂dtc)₂]₂·DABCO二聚体中，MⅡ自旋间存在短程铁磁相互作用。在白光照射下，该类配合物的光电流可提升至原水平的10²倍。自由载流子的生成主要源于从{MⅡ(R₂dtc)₂}₂·L到C₆₀的直接电荷转移。 研究发现，当磁感应强度B<1 T时，配合物的光电流随磁场增大而升高。