efficiently cocrystallized with fullerene molecules as tetrahedral monomers (6, 12), dimers (1, 7, 11), and tetramers (3, 4). Fullerene molecules form closely packed hexagonal and square layers in 1, 7, and 11, hexagonal and tetragonal 3D structures in 6 and 12, and island motifs in 3 and 4. Complexes 1-15 have a neutral ground state. However, the formation of the complexes with fullerenes changes the environment of paramagnetic Cu II and Mn II. The EPR spectra of 1, 2, 11, and 13 are essentially modified relative to those of pristine Cu(R 2 dtc) 2 because of a weak coordination of Cu II to fullerene

The first molecular complex of fullerene C60 with metal dithiocarbamate, namely, {CuII(dedtc)2}2.C60(dedtc: diethyldithiocarbamate) (1) was obtained as single crystals. Butterfly-shaped CuII(dedtc)2 molecules efficiently co-crystallized with spherical fullerene molecules to form a layered structure, in which closely packed hexagonal C60 layers alternate with the layers composed of CuII(dedtc)2 dimers. The formation of the complex with C60 changes geometry and the EPR spectrum of starting CuII(dedtc)2. Magnetic susceptibility of 1 follows the Curie-Weiss law in the 300-1.9 K range with the negative Weiss constant of -2.5 K showing a weak antiferromagnetic interaction between CuII centers in the dimers. The crystals of 1 have low dark conductivity of 10(-11) S cm-1, which is consistent with a neutral ground state of the complex. Illumination of the crystals by white light increases the photocurrent by 20-50 times. The photoconductivity spectrum of 1 has a maximum at 470 nm showing that both intermolecular charge transfer between neighboring C60 molecules and photoexcitation of CuII(dedtc)2 can contribute to photogeneration of free charge carriers. The effect of a weak magnetic field with Bo<0.5 T on the photoconductivity of 1 has been found.

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For the first time, zirconia nanocrystalline powders were derived using baddeleyite as raw material by ultrafine milling. Powders containing 19 vol% of monoclinic phase were produced by milling of baddeleyite with addition of 11 mol% of CaO. Crystallite size of tetragonal and cubic phases in resulting powders is 3-5 nm and about 15 nm in the case of monoclinic phase. Typical agglomerate's size found by scanning electron microscopy ranges from~0.1 to 10 µm. Sintered ceramics with tetragonal zirconia content of 95 vol% and crystallite size of~50 nm are produced from the powders. *

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