Molecular Motions and Phase Transitions in Plastic Closocarboranes

The quantitative model of molecular motions in two plastic phases of p-dicarbaclosodecaborane (p-C2B10H12) was proposed. In the first plastic phase (T > 303°K) the correlation times of isotropic reorientations were found to be less than 8.1 · 10−12s, and in the second plastic phase (303°K > T > 240°K) the correlation times of anisotropic reorientations around C3 axes were 3.5 · 10−10s < τc < 3.2 · 10−8s. The comparison was made with data by Leffler et al. [2] for ortho isomer of C2B10H12.