Results are reported of an investigation using synchrotron radiation into the effects of temperatures up to 1173 K on pressure-induced phase transitions in phosphorus. A cubic-type multi-anvil press was employed and a diffraction pattern in an energydispersive mode was taken for a period of time, typically 200 s, without suffering from a deterioration of the sample material. The pressure of the first transition, orthorhombic-rhombohedral (As-type), decreases with increasing temperature at a rate of 2"3 MPa K -1 and the As-type structure is stable at a pressure as low as 2-6 GPa at a temperature of 1073 K. The volume discontinuity at the transition, A V, is 10% at room temperature and remains almost unchanged with increasing temperature. The axial ratio c/a, when the rhombohedral structure is referred to the hexagonal system, changes mostly with pressure but only slightly with temperature, approaching x/6=2-45 on going to the second transition, rhombohedral-simple cubic. The pressure of this transition, in contrast to the first one, is independent of temperature but AV at this transition, 3.7%, continuously decreases with increasing temperature.

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The conduction behavior of ultrathin films (about 10 nm thick) composed of self-doped water-soluble polyaniline sulfonate (SPAN) was investigated using nano-gap electrodes under vacuum conditions. The conductance was found to be ohmic even in the high field regime up to 105 V cm−1 over a temperature range of 10–300 K. The temperature dependence of the conductance indicated that SPAN gave the extremely high value of localization length (L) = 300 nm without secondary doping, in comparison with conventional polyaniline. We propose that SPAN forms long-range highly crystalline metallic grains, and we observed intra-grain conduction due to some grains directly bridging the two nano-gap electrodes at low temperature. We conclude that inter-grain conduction becomes dominant as the temperature increases.