Anomalous electrical conductivity phenomena have been observed in thin tetracene films sandwiched between metal electrodes. The resistivity of the tetracene layer is observed to change from a high value (``off state'') to a low value (``on state'') upon the application of voltage. In the ``on state'' the resistivity is both temperature insensitive and photoinsensitive. A preliminary interpretation of this behavior is presented.

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Long-time isothermal currents in liquid crystals are in test. It is shown, that in nematic as well as isotropic pentacyanobiphenyl I 5CB/ quasi DC conductivity is observed for elevated time of measurements. The investigation of these current are presented. It is suggested that these current may originate from carrier exchange between solute molecules and electrode due to strong interface field.

Synchrotron radiation diffraction studies of meteoritic (Fe,Ni)3P crystals have been performed to reveal the ordering of the elements Fe and Ni on the three metal sites M1, M2 and M3 of the unit cell. The delta synthesis technique, which is a two-wavelength method using anomalous dispersion effects, was applied. For (Fe,Ni) phosphide crystals with different Fe:Ni ratios extracted from different meteorites, it was found that Ni occupies the M3 site and also partially the M2 site, avoiding the M1 position, whereas the M1 site is preferentially occupied by Fe. In connection with earlier results known from the literature, this metal distribution seems to be characteristic of this compound, and is independent of thermodynamic formation conditions.