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arXiv · 1910.00210

Enormous enhancement of p-orbital magnetism and band gap in the lightly doped carbyne

C. H. Wong·R. Lortz·A. F. Zatsepin
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Abstract

This paper presents a path to tailor adapted magnetic and optical properties in carbyne. Although p-orbital magnetism is generally much weaker than d-orbital magnetism, we demonstrate that the charge fluctuation of the free radical electrons triggered by a time-varying electric dipole moment leads to enormous p-orbital magnetism. By introducing 25% arsenic and 12.5% fluorine into the monoatomic carbon chain, the magnetic moment of the arsenic atom reaches 2.9 Bohr Magneton, which is ~1.3 times stronger than magnetic moment of bulk Fe. This magnetically optimized carbyne composite carries an exchange-correlation energy of 22meV (~270K). On the other hand, we convert the carbyne (in beta-form) from metallic to a semiconducting state by using anionic dopants. After doping 12.5% nitrogen and 12.5% oxygen into the beta-carbyne, the semiconducting gap of this composite is optimized at 1.6eV, which is 1.4 times larger than the band gap of bulk silicon.

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C. H. Wong, R. Lortz, A. F. Zatsepin. 2019-10-01. Enormous enhancement of p-orbital magnetism and band gap in the lightly doped carbyne. https://doi.org/10.1039/d0cp02274h

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