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arXiv · 1706.02030

A spin-gapped Mott insulator with the dimeric arrangement of twisted molecules Zn(tmdt)$_{2}$

Rina Takagi·Hiro Gangi·Kazuya Miyagawa·Biao Zhou·Akiko Kobayashi·Kazushi Kanoda
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Abstract

$^{13}$C nuclear magnetic resonance measurements were performed for a single-component molecular material Zn(tmdt)$_{2}$, in which tmdt's form an arrangement similar to the so-called ${\kappa}$-type molecular packing in quasi-two-dimensional Mott insulators and superconductors. Detailed analysis of the powder spectra uncovered local spin susceptibility in the tmdt ${\pi}$ orbitals. The obtained shift and relaxation rate revealed the singlet-triplet excitations of the ${\pi}$ spins, indicating that Zn(tmdt)$_{2}$ is a spin-gapped Mott insulator with exceptionally large electron correlations compared to conventional molecular Mott systems.

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Rina Takagi, Hiro Gangi, Kazuya Miyagawa, Biao Zhou, Akiko Kobayashi, Kazushi Kanoda. 2017-06-07. A spin-gapped Mott insulator with the dimeric arrangement of twisted molecules Zn(tmdt)$_{2}$. https://doi.org/10.1103/physrevb.95.224427

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