The synthesis, isolation and preliminary characterization of all-carbon [60]fullerene dimers C 121 and C 122 are reported.

The spin injection and transport properties of low-molecular-weight organic semiconductors such as pentacene and bis(l,2,5-thiadiazolo)-p-quinobis(l,3-dithiole) (BTQBT) were investigated utilizing planar-type spin-valve devices with half-metallic La0.67Sr0.33MnO3 electrodes. The devices showed clear spin-valve characteristics with a magnetoresistance (MR) ratio of up to 29% at 5K. The MR ratio was found to depend on the gap spacing of the electrodes, the applied bias voltage, temperature, and the crystallinity of the films. It was also affected by gas adsorption onto the films, indicating that the spins were scattered by carriers and/or radical ions in the films generated through charge transfer from gas molecules.

A novel method for crystallizing donor:acceptor blend films of small molecules in organic solar cells is developed. This method utilizes a liquid as a non‐sticking co‐evaporant during vacuum deposition. Striking enhancement in photocurrent generation is achieved in organic solar cells without exception, based on a variety of blend films produced by this method.

The 2 : 1 molecular complex of theophylline with phenobarbital crystallizes in the orthorhombic space group Pnma, with the unit-cell dimensions a = 6.991 (5), b = 25.554 (17), e = 15.129 (7) ,~. The approximate structure in the space group Pn21a was initially solved by the application of MULTAN. The correct structure was then refined in Pnma to give a final R index of 0.095. The phenobarbital molecule has mirror symmetry and participates in weak N-H... N hydrogen bonds to two symmetrically related theophylline molecules. The N(7) atom of theophylline forms a hydrogen bond with the 0(2) atom of the adjacent theophyllinc molecule, and the C(8) atom of theophylline may form a weak C-H • • • O hydrogen bond with the 0(4) atom of the adjacent phenobarbital.

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