Structural investigation of the Sm(Fe 1-x Ru x )As(O 0.85 F 0.15 ) system: A synchrotron x-ray powder diffraction study

The structural and microstructural properties of the Sm(Fe 1-x Ru x )As(O 0.85 F 0.15 ) system were investigated by means of high-resolution synchrotron x-ray powder diffraction between 10 and 300 K. The tetragonal to orthorhombic structural transition temperature decreases with the increase of the Ru content and the symmetry breaking is completely suppressed around x ~ 0.38. By combining the present results with previous magnetic and resistivity measurements, a phase diagram for the Sm(Fe 1-x Ru x )As(O 0.85 F 0.15 ) system has been drawn