Hanako Kobayashi

The magnetic susceptibilities of CsMnCl32H2O and CsMnCl32D2O

The magnetic susceptibilities of CsMnCl3·2H2O and CsMnCl3·2D2O have been measured at temperatures between 0.35 and 35 K. Above ∼9 K both salts show the broad susceptibility maximum of the one-dimensional Heisenberg antiferromagnet previously seen in the hydrate. In both cases the intrachain exchange parameter isJ/k=−3.00 K. AtTN (4.89 K for the hydrate) three-dimensional antiferromagnetic long-range order begins to develop due to weak interchain interactions with preferred alignment along theb axis. AtTN all susceptibility-temperature curves have their maximum slopes, those of χa and χc being negative. This is shown to be related to the unusual phase diagram of these systems. The limiting behavior of the susceptibilities asT → 0 K is established and interpreted. χ⊥(0) reflects the strong anisotropy of the spinwave spectrum due to the dominant intrachain interaction.

Electrical Conductivity and Some Other Properties of the Partially Oxidized Salt of the Magnus Green Salt with the Formula Pt6(NH3)10Cl10(HSO4)4

The partially oxidized salt of the Magnus green salt with the formula Pt 6 (NH 3 ) 10 Cl 10 (HSO 4 ) 4 was investigated as one-dimensional conductor. Results of the powder X-ray analysis are consistent with a chain structure proposed by Gitzel et al. The electrical conductivity shows a sharp peak between 190 and 200 K with peak value extending over 10 -1 ∼10 -4 \(\varOmega^{-1}\)cm -1 depending on samples. The metal-semiconductor transition thus found is much less gradual than those in KCP and NMP-TCNQ. In one of our samples, another transition from semiconductor to metal on cooling takes place at about 250 K.