Bicellar dispersions of chain perdeuterated 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC-d54) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC) were prepared with the molar fraction of DHPC held fixed at 20% and varying amounts of DMPC replaced by the anionic lipid 1,2-dimyristoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (DMPG). (2)H NMR spectra were examined to assess the effect of added DMPG on mixture phase behavior and morphology. Quadrupole echo decay and quadrupole-Carr-Purcell-Mieboom-Gill echo train measurements provided information about slow motions contributing to echo decay in the high temperature phases. The spectra and quadrupole echo decay properties of DMPC-d54/DHPC (4:1) and DMPC-d54/DMPG/DHPC (3:1:1) were qualitatively similar. With increasing DMPG concentration, the transition between the magnetically orientable phase and the higher temperature phase became increasingly distinct, and the spectral shape and echo decay characteristics of the high temperature bicellar phase became increasingly similar to those of DMPC-d54 in the liquid crystalline phase. The observation that DMPG changes spectra in the orientable phase incrementally while increasing the distinction between the orientable and high temperature bicellar phases provides new insights into how DMPG influences bicellar mixture morphology.

Thin-film Fe-Si-Zn libraries were investigated as negative electrode materials for Li-ion batteries using combinatorial and highthroughput techniques. X-ray diffraction and electron microprobe measurements were used to characterize the library structure. A large amorphous region exists in Si-rich compositions of this system. The electrochemistry of numerous compositions of Fe-Si-Zn materials was determined near room temperature. Both Zn and Fe additions to Si were found to suppress the formation of Li 15 Si 4 during cycling.

Fe-Si-Zn alloys prepared by ball milling were investigated as negative electrodes for Li-ion batteries. X-ray diffraction and room temperature 57 Fe Mössbauer measurements were used to characterize alloy structure. Electrochemistry of the alloys was determined at 30 • C. Formation of crystalline Li 15 Si 4 was suppressed during cycling for compositions with greater than 10 at. % Fe. Unlike sputtered films of the same composition, the incorporation of Zn in these ball milled alloys did not suppress Li 15 Si 4 formation. Instead, Zn behaved as if it were in a physical mixture with the other alloy components. This study shows that sputtered and ball milled alloys of the same composition can have very different electrochemical properties.

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