Crystal structures and phase transitions of the double perovskite oxides SrLaCuRuO6 and SrLaNiRuO6

The crystal structures of SrLaCuRuO6 and SrLaNiRuO6, were studied using synchrotron radiation powder diffraction method. The structures of both compounds have the P21/n space group at room temperature and transform to R3 at higher temperatures. The observed phase transiton temperatures are 730 and 670 K for SrLaCuRuO6 and SrLaNiRuO6, respectively.