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The structures and large nonlinear optical (NLO) responses of model alkalides, Li{[NH.sub.3]}[.sub.n]}Na (n=1-4) were studied to explore the coordination number dependence of the NLO properties in alkalides. The results suggest that to enhance the first hyperpolarizability for alkalides, the coordination number around the cation and flexibility of the complexant must be considered.

The use of the Langmuir-Blodgett (LB) technique enables centrosymmetric molecules to exhibit strong second-harmonic generation. Upon excitation of the dyes incorporated into LB films deposited on an ITO electrode, steady cathodic photocurrent was obtained. The observed quantum yield of the photocurrent strongly depends on the applied electrode potential, pH of the electrolyte, chemical structure of the dye congeners and the applied electrode potential.

Ultraviolet (UV) resonance Raman spectroscopy is used to study the location and coordination environment of Fe ions in SBA-15-type mesoporous materials. Complementary techniques have shown that Fe species are mainly located in the silica walls in Al-free SBA-15, whereas they occupy pseudo-tetrahedral or octahedral extraframework positions in Al-containing SBA-15.

The hydrolysis-controlled approach for the synthesis of aluminium-substituted mesoporous SBA-15 (Al-SBA-15) materials is presented. In this approach, the hydrolysis of the silicon precursor like tetraethyl orthosilicate is accelerated by fluoride.

Aluminum-incorporated mesoporous ethane-silica with hydrothermal ultrastability is synthesized by one-pot condensation of Al(OiPr)3 with 1,2-bis(trimethoxysilyl)ethane using octadecyltrimethylammonium chloride surfactant. The aluminum-containing mesoporous ethane-silicas are seen to be efficient catalysts for the alkylation of 2,4-di-tert-butylphenol by cinnamyl alcohol to yield a flavan.