Orthorhombic lattice deformation ofGdSr2RuCu2O8from high-resolution transmission electron microscopy and x-ray powder diffraction analysis

Abstract

${\mathrm{GdSr}}_{2}{\mathrm{RuCu}}_{2}{\mathrm{O}}_{8}$ has been synthesized using a solid state reaction and has been characterized from the structural and physical points of view. The samples exhibit the well-known superconducting and magnetic behavior; in addition, an orthorhombic modification of the ${\mathrm{GdSr}}_{2}{\mathrm{RuCu}}_{2}{\mathrm{O}}_{8}$ lattice has been detected by both high resolution transmission electron microscopy (HRTEM) and x-ray powder diffraction (XRPD) analysis. Rietveld refinement of the XRPD data has been successfully performed in the orthorhombic $\mathrm{Pmmm}$ space group yielding an ${a}_{0}\ifmmode\times\else\texttimes\fi{}{b}_{0}\ifmmode\times\else\texttimes\fi{}{c}_{0}(\ensuremath{\approx}3{a}_{0})$ type cell, with octahedral ${\mathrm{RuO}}_{6}$ polyhedra slightly distorted and rotated around $c,$ $b,$ and $a.$