Mössbauer spectrum of57Fe associated with a vacancy in aluminium

Abstract
The Mössbauer spectrum of a rapidly quenched Al-0·02 at. %−57Fe alloy hag been measured. The spectrum consists of two peaks. One corresponds to that of a solid solution of 57Fe in Al and appears at S T = 0·57 mm/s, while the other, at S T = 0·24 mm/a, is inferred to be that of 57Fe atoms associated with a vacancy. The s-electron density at the 57Fe nucleus associated with the vacancy is larger than that at the nucleus in solid solution. From the change in the recoilless fraction with temperature, the Debye temperature is estimated to be 240 K. for 57Fe in solid solution and 210 K for 57Fe atoms associated with a vacancy.