Influence of A-site ionic radii on the magnetic structure of charge-orderedLa0.5Ca0.5−xSrxMnO3manganites

2008/03/31 by Indu Dhiman, A. Das, P. K. Mishra +3 · 2 citations
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Charge (physics) #Charge ordering #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Ion #Ionic radius #Magnetic and transport properties of perovskites and related materials #Magnetic field #Magnetic structure #Magnetization #Materials science #Neutron diffraction #Order (exchange) #Orthorhombic crystal system #Physics #Rare-earth and actinide compounds #Tetragonal crystal system #Type (biology) #cond-mat.str-el

paper · pdf · doi:10.1103/physrevb.77.094440

published as Phys. Rev. B 77 (2008) 094440 · 27 pages, 10 figures

openalex publication_date 2008/03/31 · arxiv created 2008/04/24 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

The influence of the A-site ionic radii (⟨r_A⟩) on the magnetic structure has been investigated in La_0.5Ca_0.5\ensuremath-xSr_xMnO₃ compounds (0\ensuremath\leqslantx\ensuremath\leqslant0.5) using neutron diffraction, magnetization, and resistivity techniques. All compounds in the composition range x\ensuremath\leqslant0.3 crystallize in the orthorhombic structure (space group Pnma). No further structural transition is observed as temperature is lowered below 300\phantom\rule0.3em0exK. The compound x=0.4 is a mixture of two orthorhombic phases crystallizing in Pnma and Fmmm space groups. The x=0.5 compound has a tetragonal structure in the space group I4∕mcm. The charge-ordered (CO) state with CE-type antiferromagnetic order remains stable for x\ensuremath\leqslant0.3. Above x=0.3, the CE-type antiferromagnetic state is suppressed. In the x=0.4 compound, A-type antiferromagnetic ordering is found at temperatures below 200\phantom\rule0.3em0exK. Orbital ordering accompanying spin ordering is found in all the samples with x\ensuremath\leqslant0.4. The system becomes ferromagnetic at x=0.5, and no signature of orbital ordering is observed. As a function of ⟨r_A⟩, the charge-ordered state is stable up to ⟨r_A⟩\ensuremath∼1.24\phantom\rule0.3em0ex\mathrm\AA and is suppressed thereafter. The magnetic structure undergoes a transformation from CE-type antiferromagnetic state to a ferromagnetic state with an intermediate A-type antiferromagnetic state.

Citations

• Recent advances in magnetic structure determination by neutron powder diffraction
• Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides

Cited by

• Diffuse neutron scattering study of magnetic correlations in half-dopedLa0.5Ca0.5−xSrxMnO3manganites (x=0.1, 0.3, and 0.4)
• Pressure effects on the magnetic structure inLa0.5Ca0.5−xSrxMnO3(0.1≤x≤0.4)manganites