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arXiv · 0905.2951

Competition between structural distortion and magnetic moment formation in fullerene C$_{20}$

Myung Joon Han·Gunn Kim·Jae Il Lee·Jaejun Yu
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Abstract

We investigated the effect of on-site Coulomb interactions on the structural and magnetic ground state of the fullerene C$_{20}$ based on density-functional-theory calculations within the local density approximation plus on-site Coulomb corrections (LDA+$U$). The total energies of the high symmetry ($I_{h}$) and distorted ($D_{3d}$) structures of C$_{20}$ were calculated for different spin configurations. The ground state configurations were found to depend on the forms of exchange-correlation potentials and the on-site Coulomb interaction parameter $U$, reflecting the subtle nature of the competition between Jahn-Teller distortion and magnetic instability in fullerene C$_{20}$. While the non-magnetic state of the distorted $D_{3d}$ structure is robust for small $U$, a magnetic ground state of the undistorted $I_{h}$ structure emerges for $U$ larger than 4 eV when the LDA exchange-correlation potential is employed.

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Myung Joon Han, Gunn Kim, Jae Il Lee, Jaejun Yu. 2009-05-18. Competition between structural distortion and magnetic moment formation in fullerene C$_{20}$. https://doi.org/10.1063/1.3119485

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