Received ZZZ, revised ZZZ, accepted ZZZ Published online ZZZ (Dates will be provided by the publisher.)PACS 71.35.Cc, 78.20.Ci, 71.35.Aa,

Measurements of reflection, emission‐excitation, luminescence decay kinetics, and X‐ray photoelectron of Bi4Ge3O12 and Bi12GeO20 crystals have been performed, in addition to relativistic molecular orbital calculations. Both materials consist of the same elements but form different crystal structures. Based on the obtained results, the excitonic reflection structures and luminescence properties of Bi4Ge3O12 and Bi12GeO20 are discussed in comparison with each other. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

--Hybrid electric vehicles (HEVs) that emit less carbon dioxide have attracted much attention and rapidly become widespread, but further popularization of HEVs requires further technical advancement of mounted traction motors. Accordingly, our research group focuses on axial gap motors that can realize high torque density. In this paper, an axial gap motor with a novel interior permanent magnet (IPM) rotor structure is proposed and an examination of the proposed motor at the actual motor size of an HEV is presented. For comparison, we selected the newest radial gap-type 60 kW IPM synchronous motor equipped in the third-generation Toyota Prius. Under the condition that the size of the proposed motor be the same as the comparison motor, we confirmed through three-dimensional finite-element analysis that the proposed motor could output twice the maximum torque of the comparison motor. In addition, a comparison was made with a previously reported conventional IPM-type axial gap motor, and the proposed motor was found to be more effective in generating reluctance torque. Moreover, the proposed motor exhibited sufficient durability to irreversible demagnetization of the permanent magnets, to stress caused by rotating the rotor, and to unbalanced electromagnetic forces caused by axial rotor eccentricity.

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The static spin susceptibility, s SQ and s NMR , in C 60 superconductors K 3 C 60 and Rb 3 C 60 was studied using a dc superconducting quantum interference device magnetometer and 13 C NMR. We found that s SQ has a peculiar temperature ͑T͒ dependence behaving as (1ϪCT 2) with a positive constant Cϳ(1ϫ10 Ϫ6) deg Ϫ2 , contrary to the almost T independent s NMR. These observations indicate a possibility that there exist Kondolike impurities, whose Kondo temperature is ϳ500 K and whose content is ϳ0.001 spins per carbon. On the basis of these studies, the lattice constant dependence of the intrinsic spin susceptibility was established to be d s /da 0 ϭ(5.7Ϯ0.4)ϫ10 Ϫ4 emu/mol C 60 /Å in A 3 C 60 superconductors where A is an alkali metal.