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In situ 13C CP-MAS NMR measurements enabled for the first time detection of the presence and absence of water liquid phase in nanospaces of alkyl-grafted mesoporous silicas through the signals of a...

The reaction products of γ-zirconium phosphate with ethylene oxide were analyzed by solid-state 31P magic-angle spinning (MAS) NMR, and 31P and 13C solution NMR spectroscopy. γ-Zirconium phosphate can be formulated as Zr(PO4)(H2PO4)·2H2O. Ethylene oxide molecules react with the interlayer H2PO4 groups, forming diester derivatives of ethylene and/or diethylene glycols.

The interlayer surface of γ-zirconium phosphate was chemically modified by the reaction with ethylene oxide. The resulting layered organic derivative can be intercalated with LiClO4, forming solid solutions over a pretty wide range of the compositions. The ionic conductivities and the Raman spectra of the solid solutions have been studied.

Tetrahydrofuran (THF) is co-intercalated with lithium in β-ZrNCl. Two highly crystalline co-intercalation phases were obtained as single phases by the reaction of the chemically transported β-ZrNCl and lithium-naphthalene in THF. The molecular arrangements in the interlayer spaces were estimated on the basis of the one-dimensional electron-density distribution maps.

Aminopropyl groups and glucose molecules were sequentially grafted on mesoporous silica (ca. 5 nm in diameter) to synthesize a glucamine group analogue in the nanospaces. The grafted nanocomposite ...

A new cerium germanide, CeGe 3 was prepared by the reaction of a stoichiometric mixture of CeGe 2 and Ge under a pressure of 5 GPa at 1600 °C. It crystallized in a cubic unit cell with a = 4.354 (4) A, and was isotypic with CeSn 3 and CePb 3 having the Cu 3 Au structure. It showed a Curie-Weiss paramagnetic behavior from room temperature to 20 K with a Curie constant C of 0.0495 emu mol - 1 .K. The effective magnetic moment of 0.63 μ B , which was much smaller than the theoretical values of 2.54 μg for Ce3 + (4f 1 ) ions, was observed. This compound showed a metallic behavior with the resistivity of 130 and 7 μΩ.cm at room temperature and 2K, respectively.

Molecules having hydrophobic and hydrophilic groups such as 4-n-heptylaniline and 4-nonylphenol, an endocrine disrupter, fit the organic–inorganic nanostructure in alkyl-grafted MCM-41, interacting with the inorganic walls as well as the organic moiety, and thus the adsorbent achieves high molecular adsorption selectivity.

A Iayer structured manganese titanate RbXMnXTi2−XO4 (x = 0.75) of the lepidoclocite type structure was oxidized with Ce4+ in sulfuric acid solutions. Although the titanate layer was dissolved into the acidic solutions without the oxidant, the layer showed high resistivity against the dissolution with the presence of Ce4+ ions, even in the same acidic conditions. A portion of the Rb ions were deintercalated corresponding to the amount of Mn3+ oxidized to Mn4+ in the manganese titanate layers.

Photoelectron emission from Au was measured in ambient atmosphere under irradiation of ultraviolet light from a Hg lamp. The emission was greatly influenced by the adsorption of organic and inorganic vapors. The adsorption of cyclohexene showed a significant, but gradual increase of photoelectron emission. On the other hand, the adsorption of acetone reduced photoelectron emission irreversibly to near zero. The change of the photoelectron emission could be interpreted in terms of the change of the work function.

Alkali metal intercalated compounds of a layer structured perovskite, KCa2Nb3O10, have been prepared by the reaction with n-butyllithium or alkali metal azides, AN3 (A = Li and Na). The magnetic susceptibility measurements showed that the compounds became superconductors with transition temperatures ranging from 3 - 6 K.

Lithium-manganese-cobalt oxide, Li(Lix/3MN2x/3Co1−x)O2 (0 ≤ x ≤ 1) was prepared as a solid solution between the two kinds of layer structured end members, LiCoO2 and Li2MnO3. Excess lithium carbonate or lithium hydroxide should be added to the mixture on calcination at 900 - 1000 °C to obtain the solid solutions. The resulting layer structured solid solutions can be used as a cathode material for secondary lithium batteries.

New types of intercalated complexes are synthesized by the reaction of MPS3 layer crystals (M=Mg, Zn, Mn) with n-alkylamines (CnH2n+1NH2, n=1–8). The amines are adsorbed on the interlamellar surfaces of the MPS3 crystals to form two different types of complexes of increased values in basal spacing. The spacing value of the first type of complexes is independent of the number of carbon atoms in alkyl chain of the amines, and the value of the second type of complexes increases with the number of the carbon atoms. The possible arrangements of the amines in the interlayer region are proposed for these types of complexes.

Basic copper acetate, Cu2(OH)3(OCOCH3)·H2O has the layer structure of the botallackite type. The acetate ions are located between the positively charged copper hydroxide layers and exchangeable with various anions such as NO3−, ClO4−, Cl−, Br−, I− and carboxylate ions. The exchange reactions are topotactic and some are reversible.