Effect of the internal pressure and the anti-site disorder on the structure and magnetic properties of ALaFeTiO6 (A=Ca, Sr, Ba) double perovskite oxides

► Anti-site disorder was revealed in (Ca,Sr,Ba)LaFeTiO6 double perovskites. ► Mössbauer spectroscopy revealed a dependence of the quadruple splitting and the cation size mismatch. ► Weak ferromagnetism is evidenced due to internal pressure and anti-site disorder.