M$ouml$ssbauer studies of gold manganese alloys

The 77 keV 197 Au Mössbauer resonance has been investigated at 4.2 K for all the phases of the gold manganese system which could be retained at room temperature. The isomer shift increases linearly with manganese concentration due to a transfer of electrons from the manganese atoms to the gold atoms. Quadrupole interactions are observed for 197 Au in βMn, Au 2 Mn and AuMn 2 , and the values obtained are consistent with a simple point charge model. Analysis of the hyperfine magnetic fields for the magnetically ordered alloys in terms of a model whereby the field is determined by the geometrical arrangement of nearest neighbour manganese spins, yields a field per manganese unpaired electron of approximately 55 kOe,