Radioactive Mn-57(+) ions have been implanted at the ISOLDE facility into variously doped silicon single crystals to study the lattice location and electronic configuration of Fe-57 daughter atoms by Fe-57 Mossbauer emission spectroscopy. Two single lines in the spectra are assigned to substitutional Fe-s and interstitiaI Fe-i, respectively. The isomer shift, i.e. electron density, for Fe-i has been found to depend on the doping of the crystals, this is attributed to the 0/+ band gap state of Fe-i. A model for the creation of both Fe-s and Fe-i in different charge states by the beta(-)-decay of ion implanted Mn-57 is proposed.