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arXiv · 1102.3330

Calculation of magnetic exchange couplings in S=3/2 honeycomb system Bi$_3$Mn$_4$O$_{12}$(NO$_3$)} from first principles

Hem C. Kandpal·Jeroen van den Brink
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Abstract

Absence of magnetic ordering in Bi$_3$Mn$_4$O$_{12}$(NO$_3$), (BMNO) which has a magnetic subsystem that consists of honeycomb bi-layers of Mn$^{4+}$ ions with spin S=3/2, has raised the expectation that its ground state is strongly frustrated due to longer-range antiferromagnetic interactions. We calculate the magnetic exchange coupling constants of the BMNO complex within a density functional approach and find that the dominating interactions between Mn spins are the antiferromagnetic nearest-neighbor $J_1$ and interlayer interaction $J_c$. The largest interaction is $J_c$, which substantially exceeds $J_1$. Longer-range interactions are antiferromagnetic, but only weakly frustrating.

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Hem C. Kandpal, Jeroen van den Brink. 2011-03-31. Calculation of magnetic exchange couplings in S=3/2 honeycomb system Bi$_3$Mn$_4$O$_{12}$(NO$_3$)} from first principles. https://doi.org/10.1103/physrevb.83.140412

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