Moessbauer studies of baotite and bafertisite

The Moessbauer effect was used to study silicate minerals of baotite and bafertisite at 298 K and 95 K. Each spectrum of baotite at 298 K and 95 K consists of two doublets, and they are contributed from Fe2+ and Fe3+ in the octahedral Ti-sites, respectively. Each spectrum of bafertisite at 298 K and 95 K is composed of two doublets, and they are mainly caused by Fe2+ in the octahedral Fe(I)- and Fe(II)-sites, respectively. The average effective ionic radii of the Ti sites in baotite and the Fe(I)- and Fe(II)-sites in bafertisite were estimated based on the correlation of the isomer shifts with the average effective ionic radii in silicates, and they are 0.56 deg. A, 0.73 deg. A and 0.73 deg. A, respectively