- Reflection and absorption edge spectra in mercurous halide single crystals
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The reflection and absorption edge spectra in Hg2I2 and Hg2Br2 single crystals were measured in the visible and near ultraviolet region at various temperatures. The exciton transition of the lowest energy was as
- Jiang, Xue Yin,Itoh, Tadashi,Goto, Takenari
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- Raman spectroscopic studies of metal-metal halide molten mixtures: The mercury-mercury(II) halide systems
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Raman spectra of molten HgX2-Hg (X = Cl, Br, I) systems have been obtained at compositions up to 30 mol % in Hg from 550 to 818 K. The dissolution of mercury in mercury halides gives rise to resonance-enhanced Raman bands which were interpreted to account for Hg2Xa type molecular species formed in all mercury compositions and Hg3X2 type molecules formed at high mercury mole fractions. Spectra were also obtained from HgX2-HgX′2-Hg (X = F, Cl, Br, I) mixtures and were attributed to mixed mercury(I) (sub)halide molecules Hg2XX′ formed in the melt. The Hg2X2 and Hg2XX′ molecules possess a linear symmetry, and the Hg-Hg stretching frequencies for all 10 molecules were found to be between ~ 180 cm-1 (Hg2F2) and ~ 100 cm-1 (Hg2I2). A linear Hg3 chain is formed in the Hg3X2 molecules bound to two terminal halides. The formation of Hg3 chains was further confirmed by the Raman spectra of Hg3(AlCl4)2 melts. It is suggested that in the melt mixtures intermolecular interactions between HgX2 and Hg2X2 molecules lead to an alteration of oxidation states which account for a hopping like conduction.
- Voyiatzis,Papatheodorou
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p. 1945 - 1951
(2008/10/08)
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