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Role of Conduction Electrons in the ortho-KC$_{60}$ Polymer

T. Ogitsu·K. Kusakabe·S. Tsuneyuki·Y. Tateyama
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Abstract

We present first-principles band calculations as well as structural optimization of the orthorhombic K$_1$C$_{60}$ polymerized phase. We found three-dimensional inter-fullerene bonding/anti-bonding characters consisting of $t_{1u}$ molecular orbitals with $p$-like symmetry in the conduction bands. The formation of the four-membered ring connecting the fullerenes lifts the $p_x$ band from the continuous $p_y$-$p_z$ band, where the z-axis is parallel to the chain. The asymmetry between $p_x$ and $p_y$ may play an important role in binding the chains with the rotational configuration proposed by Stephens et al.

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T. Ogitsu, K. Kusakabe, S. Tsuneyuki, Y. Tateyama. 1997-12-24. Role of Conduction Electrons in the ortho-KC$_{60}$ Polymer. https://arxiv.org/abs/cond-mat/9712285

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