The structure of zinc chloride complexes with different ratios of chloride to zinc, formed in concentrated ZnCl2 aqueous solutions, were determined from large-angle X-ray scattering using concentrations of the chloride complexes estimated by complementary Raman spectroscopic measurements. The highest chloro complex, [ZnCl4]2-, is tetrahedral with a Zn-Cl bond length of 2.294(4) Å. The trichloro complex, [ZnCl3]-, which coordinates one water molecule, is pyramidal with the Cl-Zn-Cl angle 111°. The Zn-Cl and the Zn-H2O bonds are 2.282(4) and 1.9 Å, respectively. The two lower complexes, [ZnCl2] and [ZnCl]+ , cannot be separated by Raman spectra. The average Zn-Cl distance in these complexes is 2.24 Å, and the average Zn-H2O distance is 1.9 Å. In [Zn(H2O)6]2+ the Zn-H2O distance is 2.15 Å.

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12CaO . 7Al 2 O 3 (C12A7) composed of nanosize cage structure can clathrate oxygen radicals (O À ) and has a high potential to application of strong oxidizing catalysis. In the present report, we demonstrate a fabrication route to C12A7 fine powders by Chemical Solution Deposition method in order to enhance the catalytic reactivity. Aluminum sec-butoxide, calcium nitrate tetrahydrate, acetylacetone, 2-methoxyethanol, and nitric acid were used as raw materials. Precursor solution was dried and annealed at 8001-9001C in air or O 2 atmosphere. Crystalline C12A7 powders were obtained by annealing at 9001C in O 2 atmosphere. Scanning electron microscope and transmission electron microscope images of the obtained powders revealed C12A7 particles were sintered and formed several micrometer particles with many pores. BET specific surface area of the powders was 4.2 m 2 /g. Possibility for synthesizing C12A7 powder with higher specific surface area by the solution process was indicated.

The stability constants, [31, of the monochloride complex of Sm(llI) have been determined in mixed system of methanol and water at 1.00 mol dm -3 ionic strength using a solvent extraction technique. The values of ~3~ increase with an increase in the mote fraction of methanol (Xs) in the mixed solvent system when 0<_Xs_<0.351. The interionic distance of Sm3+-CI -(dsm.cl) in the mixed solvent system was estimated by applying the Gibbs' free energy derived from L3~ to a Born-type equation. It was determined that an inflection point of the variation in the estimated ds~.cl against X s was present in the vicinity ofX s = 0.054. The inflection point ofdsm_Cl shows a value ofX s between those OfdEu.Cl and dNd.Ct previously obtained by us.

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