Orbital-spin order and the origin of structural distortion in MgTi2O4
نویسندگان
چکیده
We analyze electronic, magnetic, and structural properties of the spinel compound MgTi2O4 using the local density approximation+U method. We show how MgTi2O4 undergoes to a canted orbitalspin ordered state, where charge, spin and orbital degrees of freedom are frozen in a geometrically frustrated network by electron interactions. In our picture orbital order stabilizes the magnetic ground state and controls the degree of structural distortions. Our ground-state theory provides a consistent picture for the dimerized phase of MgTi2O4, and might be applicable to frustrated materials in general.
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