Crystal structure and electronic transport of (formula presented)

The crystal structure of (formula presented) isomer I at 298 K has been determined by Rietveld refinement for x-ray powder diffraction with synchrotron radiation. Isomer I shows a simple cubic structure (sc: (formula presented) with a lattice constant a of 15.78(1) Å. The (formula presented) axis of a (formula presented) cage aligns along the [111] direction of this crystal lattice. The (formula presented) cage is orientationally disordered to satisfy a (formula presented) symmetry along [111], which is requested in this space group. The large thermal parameter for the Dy atom estimated from the x-ray diffraction probably reflects a large disorder caused by a floating motion of the Dy atom inside the (formula presented) cage as well as a ratchet-type motion of the (formula presented) molecule. The electronic transport of thin film of (formula presented) shows a semiconducting behavior. The energy gap (formula presented) is estimated to be 0.2 eV. Further, the variation of valence from (formula presented) to (formula presented) is found by metal doping into the (formula presented) crystals.