Hydrogen interaction with solid iridium complexes IrXH2(PPr i3)2 (X = Cl, I) was investigated. Gaseous hydrogen was found to react reversibly with solid chloro-iridium complex IrClH2(PPri3)2, forming IrClH2(PPri3)2H2 The relative partial molal enthalpy and entropy were obtained from equilibrium isotherms at different hydrogen concentrations. The decrease in entropy with increasing hydrogen concentration and the absence of plateaus in the equilibrium isotherms were consistent with a single phase solid solution with two chemical components. Hydrogen release from solid iodo-iridium complex IrIH2(PPri3)2H2 was not observed at temperatures up to 350 K, indicating stronger hydrogen bonding.

Substrate effects on the measurement of thin film mechanical properties by nanoindentation methods have been studied experimentally using a model soft film on hard substrate system: aluminum on glass. The hardness and elastic modulus of aluminum films with thicknesses of 240, 650, and 1700 nm sputter-deposited on glass were systematically characterized as a function of indenter penetration depth using standard nanoindentation methods. Scanning electron and atomic force microscopy of the hardness impressions revealed that indentation pileup in the aluminum is significantly enhanced by the substrate. The substrate also affects the form of the unloading curve in a manner that has important implications for nanoindentation data analysis procedures. Because of these effects, nanoindentation measurement techniques overestimate the film hardness and elastic modulus by as much as 100% and 50%, respectively, depending on the indentation depth. The largest errors occur at depths approximately equal to the film thickness.

CuCl2 and FeCl3 graphite intercalation compounds were prepared by a gas phase reaction method using different carbon host materials. The effect of the microstructure of carbon host materials on the amount of intercalation and the distribution of intercalant was investigated using x-ray diffraction and electron microprobe analysis. For a fiber sample with a core region of onion skin structure in the cross section, a lower concentration of intercalant was measured in the core region. For fiber samples with an oriented-core transverse microtexture, different intercalant distributions along the long axis (oriented-core direction) and the short axis of the elliptical cross section were found.