Probing structural phase transitions of crystalline C60 via resistivity measurements of metal film overlayers

The electrical resistance of thin silver films deposited on C60 crystals shows anomalies near 261, 240, and 100 K. These temperatures coincide, respectively, with the bulk rotational, surface rotational, and quenched disorder structural phase transitions of crystalline C60. Films of other metals on C60 show similar behavior. Our findings demonstrate that thin metal film overlayers are sensitive probes of the structural phase transitions in C60, and also provide evidence for a novel structural-electronic interaction at the metal/C60 interface.