Structural and magnetic properties of RTiNO2 (R=Ce, Pr, Nd) perovskite nitride oxides

摘要: Neutron powder diffraction indicates that CeTiNO{sub 2} and PrTiNO{sub crystallize with orthorhombic Pnma symmetry (Ce: a=5.5580(5), b=7.8369(7), c=5.5830(4) A; Pr: a=5.5468(5), b=7.8142(5), c=5.5514(5) A) as a result of a{sup –}b{sup +}a{sup –} tilting the titanium-centered octahedra. Careful examination NPD data, confirms absence long range anion order in both compounds, while apparent superstructure reflections seen electron patterns provide evidence for short order. Inverse magnetic susceptibility plots reveal RTiNO{sub (R=Ce, Pr, Nd) compounds are paramagnetic Weiss constants vary from −28 to −42 K. Effective moments 2.43 μ{sub B}, 3.63 3.47 respectively, line values expected free rare-earth ions. Deviations Curie–Weiss behavior occur below 150 K 30 NdTiNO{sub driven by anisotropy, spin–orbit coupling, crystal field effects. - Graphical abstract: The structure magnetism oxide nitride perovskites have been explored. average is shown be random distribution ions −}b{sup −}more » octahedra, but shows All three deviations Curie law R=Ce R=Nd. Highlights: • Pr) prepared their structures determined. Diffraction measurements indicate cis-order O N, no Compounds CeTiO{sub 2}N NdTiO{sub deviate K, respectively.« less