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Polarized reflectivity spectra of CaMoO 4 and CaWO 4 single crystals have been measured up to 30 eV by using synchrotron radiation as a light source. The optical constants for a-and c-axes are derived from the reflectivity spectra by a Kramers -Kronig analysis. A clear correspondence is found in the main structures of the optical spectra between molybdate and tungstate. It is revealed that the lowest bands peaking at 5.0 eV in CaMoO 4 and at 6.0 eV in CaWO 4 consisit of some fine structures with distinct dichroism. They are attributed to the joint density-of-states; in other words, no structures indicative of exciton transition are found at the fundamental absorption edge. From the comparison of the spectral profiles in CaMoO 4 and CaWO 4 , the structures below 10 eV are ascribed to the transitions from the O 2p valence band to the conduction band mainly made of Mo 4d (W 5d) states, while those above 10 eV are assigned to the transitions to the Ca conduction band. The polarization dependence of the structures below 10 eV is explained well in terms of the intramolecular transition in an oxyanion complex in the scheelite crystal. The energy band structure of CaWO 4 is discussed taking into account of the previous results such as the thermostimulated luminescence and the two-photon excitation.

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We prepared hydrazone-palladium(II) complexes of [PdCl2(HL(n))] and [PdCl(L(n))] (n = 1-3) by the reaction of [PdCl2(cod)] or [PdCl2(PhCN)2] and the hydrazone ligands of HL(n) {N'-(pyridin-2-ylmethylene)picolinohydrazide (HL(1)), N'-[1-(pyridin-2-yl)ethylidene]picolinohydrazide (HL(2)), and N'-[(6-methylpyridin-2-yl)methylene]picolinohydrazide (HL(3))}. The structures of the complexes were determined by X-ray analysis. The hydrazone ligands had κN(py1),κN(imine) and κN(amidate),κN(py2) bidentate coordination modes in [PdCl2(HL(n))] (1, n = 1; 2, n = 2) and in [PdCl2(HL(3))] (3), respectively. In contrast, tridentate coordination modes of κN(py1),κN(imine),κN(py2) and κN(py1),κN(amidate),κN(py2) were observed in [PdCl(L(n))] (4, n = 1; 5, n = 2) and in [PdCl(L(n))] (6, n = 1; 7, n = 2; 8, n = 3). Thermal conversion of complexes 1-3 to complexes 6-8 proceeded in acetonitrile. Complexes 4 and 5 were obtained from complexes 1 and 2, respectively, in a basic acetonitrile solution under dark conditions. Complex 4 reverted immediately to complex 1 in an acidic acetonitrile solution that included hydrochloric acid. However, under room light, in the basic acetonitrile solution that included trimethylamine, complex 4 converted photochemically to complex 6. The thermochromic or vapochromic structure conversion of these complexes also occurred in the solid state. On heating at 180 °C, the color of the crystals of complexes 1, 2, and 3 changed from yellow to orange in the solid state. (1)H NMR and/or UV-vis absorption spectroscopy confirmed that the orange complexes 6-8 were produced. The reddish-orange crystals of complexes 4 and 5 were exposed to hydrogen chloride vapor to yield the yellow products of complexes 1 and 2, respectively.

Our cases confirmed the correlation between the risk categories and the prognosis. A complete resection with sufficient margin must be confirmed even in low-risk cases to prevent local recurrence. Since high-risk patients showed poor prognosis, the adjuvant treatment with chemotherapeutic regimens must therefore be further studied for high-risk patients.