So far available experimental data on the magnetic ground state and transport behaviors of CaCrO3 are conflicting, suggesting that the electronic structure may be fragile against intrinsic or external perturbations. In this work we perform full-scale first principles calculations on the magnetic ground state and electronic structure of CaCrO3. It is revealed that the electronic structure and spin order are sensitive to the on-site Coulomb interaction and lattice distortion. The magnetic ground state is of the marginal stability, close to the boundary between various antiferromagnetically ordered phases. A crossing over the magnetic boundaries and associated metal-insulator transitions can be allowed by even weak lattice distortion (compressive strain) on the ab plane. The numerical results suggest that the on-site Coulomb interaction and lattice distortion represent two major ingredients of physics to determine the magnetic ground state, thus reasonably interpreting the scattered experimental data on the spin order and transport behaviors for CaCrO3.

Articles you may be interested inStructural, electrical, magnetic, and thermal studies of Cr-doped La 0.7 Ca 0.3 Mn 1 − x Cr x O 3 ( 0 ≤ x ≤ 1 ) manganites J. Appl. Phys. 107, 083905 (2010); 10.1063/1.3342462 Effect of Li doping on the magnetotransport properties of La 0.7 Ca 0.3−y Li y MnO 3 system: Decrease of metal-insulator transition temperature Variable-range hopping conductivity and absence of a true metal-insulator transition in La 0.7−δ Ca 0.3 Mn 1−y Fe y O 3The structure, ionic valences, magnetism, and magneto-transport behaviors of mixed valence oxides La 1Àx Ca x Mn 1Àx Ru x O 3 are systematically investigated. The simultaneous substitutions of La 3þ and Mn 3þ ions by Ca 2þ and Ru 4þ , respectively, are confirmed by the structural and ionic valence characterizations, excluding the presence of Mn 4þ and Ru 3þ ions. The enhanced ferromagnetism, induced metal-insulator transition, and remarkable magnetoresistance effect are demonstrated when the substitution level x is lower than $0.6, in spite of the absence of the Mn 3þ -Ru 4þ e g -orbital double-exchange. These anomalous magnetotransport effects are discussed based on the competing multifold interactions associated with the Mn 3þ -Ru 4þ super-exchange and strong Ru 4þ -Ru 4þ hopping, while the origins for the metal-insulator transition and magnetoresistance effect remain to be clarified. V C 2014 AIP Publishing LLC.