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Commensurate and modulated magnetic phases in orthorhombic A1C60

E. J. Mele·G. V. Krishna·S. C. Erwin
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Abstract

Competing magnetically ordered structures in polymerized orthorhombic A1C60 are studied. A mean-field theory for the equilibrium phases is developed using an Ising model and a classical Heisenberg model to describe the competition between inter- and intra-chain magnetic order in the solid. In the Ising model, the limiting commensurate one-dimensional and three-dimensional phases are separated by a commensurate three-sublattice state and by two sectors containing higher-order commensurate phases. For the Heisenberg model the quasi-1D phase is never the equilibrium state; instead the 3D commensurate phases exhibits a transition to a continuum of coplanar spiral magnetic phases.

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E. J. Mele, G. V. Krishna, S. C. Erwin. 1994-12-02. Commensurate and modulated magnetic phases in orthorhombic A1C60. https://doi.org/10.1103/physrevb.52.12493

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