A μSR study of valence fluctuations in Fe3O4

New µSR measurements on Fe3O4, showing a temperature shift of the "247 K anomaly" in applied fields, demonstrate muon-conduction-electron cross-relaxation and yield a 0.11 eV barrier for near-neighbor B-site electron transfer above the Verwey transition. µSR relaxation rates and the possibility of molecular-polaron formation are discussed