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arXiv · 1411.3026

First-principles study of an organometallic S=1/2 kagome compound

Zheng Liu·Jia-Wei Mei·Feng Liu
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Abstract

Cu(1,3-benzenedicarboxylate) [Cu(1,3-bdc)] contains structurally perfect kagomé planes formed by Cu$^{2+}$ ions without the presence of diamagnetic defects. This organometallic compound should have served as a precious platform to explore quantum frustrated magnetism, yet the experimental results so far are mysterious, leading to questions such as "Is Cu(1,3-bdc) just a trivial weak ferromagnet?". Using the the density functional theory, we have systematically studied the electronic and magnetic properties of Cu(1,3-bdc), putting forth a theoretical basis to clarify this novel material. We present numerical evidences of a dominating antiferromagnetic (AFM) exchange between nearest-neighbor (NN) Cu$^{2+}$ as experimentally extracted from the high-temperature susceptibility data. We further show that beyond the NN AFM exchange, the additional interactions in Cu(1,3-bdc) have similar strength as those in the well-studied kagomé antiferromagnet, Herbertsmithite, by designing a comparative study. In the end, the origin of the phase transition and FM signals observed under low temperature is discussed based on the DFT results.

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Zheng Liu, Jia-Wei Mei, Feng Liu. 2015-10-01. First-principles study of an organometallic S=1/2 kagome compound. https://doi.org/10.1103/physrevb.92.165101

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