Thermodynamics of the silicon type I clathrates: Ba8Si46 and Na8Si46

INOR 361

Cathie L. Condron, clcondron@ucdavis.edu1, Tamas Varga2, Alisha Clark3, Charles E. Lesher3, Alexandra Navrotsky2, and Susan M. Kauzlarich1. (1) Department of Chemistry, University Of California Davis, One Shields Ave., University of California, Davis, CA 95616, (2) Department of Chemistry and Thermochemistry Facility and NEAT ORU, University California Davis, One Shields Ave. University of California, Davis, CA 95616, (3) Department of Geology, University of California Davis, One Shields Ave. University of Californa, Davis, CA 95616
Binary and ternary clathrate phases provide an exciting area of research. Type I clathrates crystallize in the cubic space group Pm-3n and exhibit rich crystal chemistry as well as a wide variety of physical properties. Examples are superconductivity, thermoelectricity, and the potential for band gap engineering. High-temperature oxide melt drop solution calorimetry was used to study the energetics of formation for Ba8Si46 and Na8Si46. Ba8Si46 was prepared using high pressure techniques, while Na8Si46 can be prepared by thermal decomposition of the Zintl phase NaSi. The synthesis, composition, structure characterization, and thermodynamics will be presented and discussed.
 

Solid State and Solid State Materials
7:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Division of Inorganic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006