Anticoincidence measurement of 57Fe Mössbauer spectra obtained after 57Mn implantation: application to Fe in α-Al2O3

A new detection system was developed using a gas-filled resonance counter operated in anticoincidence with a plastic scintillation detector for 57Fe Mossbauer spectroscopy using a short-lived 57Mn (T 1/2 = 1.45 min) beam. We have succeeded in measuring 57Fe Mossbauer spectra obtained after 57Mn implantation into single-crystalline α-Al2O3 at 92, 193, and 298 K, with an adequate ratio of the resonance peak against the background by applying this detection system, in spite of the extremely low implantation dose. Final positions of Fe atoms in α-Al2O3 are discussed and compared with the results of the ab initio density functional calculations.