Crystal and magnetic structure of the La1-xCaxMnO3 compound (x=0.8,0.85)

Article

关键词: COLOSSAL MAGNETORESISTANCE;    NEUTRON-DIFFRACTION;    PHASE-SEPARATION;    WIGNER-CRYSTAL;    BI-STRIPE;    CHARGE;    TRANSITION;    TRANSPORT;    TEMPERATURE;    OXIDES;   

DOI  :  10.1103/PhysRevB.65.064413

来源: SCIE

【 摘 要 】

We studied the crystal and magnetic structure of the La1-xCaxMnO3 compound for x = 0.8 and x = 0.85. At T=300 K both samples are paramagnetic with crystallographic symmetry Pnma. At low temperatures they undergo a monoclinic distortion from orthorhombic Pnma-type structure with a (p)root2 x 2 a (p) x a (p) root2- to a monoclinic structure with (a (p) root2 x 2 a (p) x a (p) root2, beta = 90 + epsilon similar to 91.4degrees) and P2perpendicular to/m space group below T-N. The onset of the structural transformation coincides with the development of the C-type long range antiferromagnetic order with propagation vector k = (1/2,0, 1/2). The monoclinic unit cell allowed us to determine the direction of the Mn magnetic moment with respect to the crystallographic axes: it is perpendicular to the propagation vector mperpendicular to k = (1/2, 0,1/2). The amplitude of the ordered magnetic moment at T = 1.6 K is found to be 2.53(2) and 2.47(2)mu(B) for x = 0.8 and 0.85, respectively.

【 授权许可】

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