Studies on the Magnetic Ground State of a Spin M\"obius Strip

Graham N. Newton; Norihisa Hoshino; Takuto Matsumoto; Takuya Shiga; Motohiro Nakano; Hiroyuki Nojiri; Wolfgang Wernsdorfer; Yuji Furukawa; Hiroki Oshio

arXiv · 1607.06130

Studies on the Magnetic Ground State of a Spin M\"obius Strip

Graham N. Newton·Norihisa Hoshino·Takuto Matsumoto·Takuya Shiga·Motohiro Nakano·Hiroyuki Nojiri·Wolfgang Wernsdorfer·Yuji Furukawa·Hiroki Oshio

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Abstract

Here we report the synthesis, structure and detailed characterisation of three n-membered oxovanadium rings, Na$_n$[(V=O)$_n$Na$_n$(H$_2$O)$_n$($\alpha$, $\beta$, or $\gamma$-CD)$_2$]$m$H$_2$O (n = 6, 7, or 8), prepared by the reactions of (V=O)SO$_4$$\cdot$$x$H$_2$O with $\alpha$, $\beta$, or $\gamma$-cyclodextrins (CDs) and NaOH in water. Their alternating heterometallic vanadium/sodium cyclic core structures were sandwiched between two CD moieties such that O-Na-O groups separated neighbouring vanadyl ions. Antiferromagnetic interactions between the $S$ = 1/2 vanadyl ions led to $S$ = 0 ground states for the even-membered rings, but to two quasi-degenerate $S$ = 1/2 states for the spin-frustrated heptanuclear cluster.

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Graham N. Newton, Norihisa Hoshino, Takuto Matsumoto, Takuya Shiga, Motohiro Nakano, Hiroyuki Nojiri, Wolfgang Wernsdorfer, Yuji Furukawa, Hiroki Oshio. 2016-07-20. Studies on the Magnetic Ground State of a Spin M\"obius Strip. https://arxiv.org/abs/1607.06130

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