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Describes the reduction routes of inorganic complexes and metal-alkyl complexes, using data obtained from IR and UV-vis spectroelectrochemical measurements and cyclic voltammetry at variable temperatures. Materials and preparations; IR spectral changes in the carbonyl stretching region during the reduction; Establishment of a one-electron reduction.

Focuses on an experiment in which a spectroscopic and photophysical study of a rhenium complex was done with the aim of tuning the excited state properties by ligand variations. Explanation of halide influences on the complex; Emissive nature of the complex at 80K in a glass; Revelations from nanosecond time-resolved absorption spectroscopy of the rhenium complex.

Discusses the photoreactions of (CO)5ReMn(CO)3(alpha-diimine) complexes. Effects of irradiation into the MCLT absorption band in CH2Cl2; Formation of final products; Similarity of activation volumes to those of thermal CO-loss reactions in analogous complexes; Picosecond and nanosecond photolysis.

Presents a nanosecond to microsecond time-resolved UV-Vis and IR spectroscopic study of the Re(benzyl)(CO)3(iPR-DAB) complex. Product absorption band; Precursors to the photochemically formed radicals; Features of the whole family of photoreactive metal-alkyl and metal-metal diimine complexes.

Raman microscopy has been applied to study the preparation of shaped Mo/Al2O3 catalysts. The speciation of different Mo complexes over γ-Al2O3 support bodies was followed in time after pore volume impregnation with aqueous solutions containing different Mo complexes. The addition of NO3 to the impregnation solutions allows for a quantitative Raman analysis of the distribution of different complexes over the catalyst bodies as this ion can be used as an internal standard. After impregnation with an acidic ammonium heptamolybdate (AHM) solution, the strong interaction between Mo7O246- and Al2O3 results in slow transport of this complex through the support and extensive formation of Al(OH)6Mo6O183- near the outer surface of the support bodies. This may be prevented by decreasing the interaction between Mo and Al2O3. In this way, transport is facilitated and a homogeneous distribution of Mo is obtained on a reasonable time scale. A decrease in interaction between Mo and Al2O3 can be achieved by using alkaline impregnation solutions or by the addition of complexing agents, such as citrate and phosphate, to the impregnation solution. In general, time-resolved in situ Raman microscopy can be a valuable tool to study the physicochemical processes during the preparation of supported catalysts. [ABSTRACT FROM AUTHOR]