ELECTRONIC-STRUCTURE OF BARIUM FULLERIDES

Compounds of the form BaxC60 with x=3 and 6 resulting from the reactio n of C60 with Ba have been prepared and characterized by photoemission . For x=3 the t1u band derived from the LUMO of C60 is filled, resulti ng in an electronic structure similar to that of K6C60. Upon further e xposure to Ba, the t1g band becomes occupied, but the system remains m etallic at the largest Ba concentration that could be achieved. The su perconductivity is associated with the t1g band.