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

Abstract

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.

Coordination chemistry on carbon surfaces

“…fullerene and the corresponding metal dithiocarbamate (Fig. 16) [261,262]. According to optical and electron paramagnetic resonance (EPR) spectroscopy these species have a neutral ground state.…”

Mono urotropine adducts of some binary zinc xanthates and dithiocarbamates: solid-state molecular structures and supramolecular self-assembly

“…There are literature precedents for III whereby III has been isolated as a co-crystal with fullerene (C 60 ) with chlorobenzene as the occluded solvent; the ratio of the species is 2 : 1 : 1 [46]. Figure 11 shows an overlay diagram of III with the two molecules from the literature and several conformational differences are evident.…”

Cyan titania nanowires: Spectroscopic study of the origin of the self-doping enhanced photocatalytic activity

“…Measurements in the 105-420 GHz frequency range were carried out on a home-made quasi optical spectrometer [26,27]. The high sensitivity of the millimeter-wave setup allows detection of ppm concentration of paramagnetic centers [28,29,30,31]. The possibility to observe EPR at different frequencies allows the precise determination of microscopic properties of the EPR centers [32,33,34,35,36].…”