Light Atom Location in Filled Skutterudites

Thermoelectric materials offer tremendous potential for the conversion of waste heat energy into useful electrical energy. We are currently engaged on a collaborative project that seeks to develop skutterudites for energy recovery in vehicle exhaust streams. In the course of this work, we have succeeded in introducing lithium filler atoms into a series of isoelectronic mixed-metal skutterudites. This produces significant changes in electrical and thermal transport properties. However, owing to the low X-ray scattering power of lithium we are unable to locate the filler atom by X-ray methods. We wish to exploit the capacity of neutrons to locate lithium in the presence of heavy atoms, to carry out a detailed structural study of a series of isostructural lithium-containing skutterudites.