Mössbauer effect used to study rare-earth oxides synthesized by a high-pressure method

Abstract

In the present paper the double rare-earth oxide solid solutions (EuR)${\mathrm{O}}_{3}$ (R=Gd, Dy, Ho, Er, Yb, Lu) are synthesized for the first time with a combination of high pressure and high temperature (3.0 GPa and 1080--1250 \ifmmode^\circ\else\textdegree\fi{}C). The analysis of x-ray diffraction shows that all products are B type (monoclinic) structures of single phase. Considering \ensuremath{\eta}\ensuremath{\ne}0 the $^{151}\mathrm{Eu}$ M\"ossbauer spectra were fitted by twelve transition lines. It is shown that the isomer shift depends on the unit-cell volume ${V}^{1/3}$ in a linear fashion.