Spin Frustration in an Organic Radical Ion Salt Based on a Kagome-Coupled Chain Structure

J Am Chem Soc. 2016 Aug 31;138(34):10738-41. doi: 10.1021/jacs.6b05079. Epub 2016 Aug 18.

Abstract

Electro-oxidation of the quinoidal bisdithiazole BT in dichloroethane in the presence of [Bu4N][GaBr4] affords the 1:1 radical ion salt [BT][GaBr4], crystals of which belong to the trigonal space group P3. The packing pattern of the radical cations provides a rare example of an organic kagome basket structure, with S = 1/2 radical ion chains located at the triangular corners of a trihexagonal lattice. Magnetic measurements over a wide temperature range from 30 mK to 300 K suggest strongly frustrated AFM interactions on the scale of J/kb ∼ 30 K, but reveal no anomalies that would be associated with magnetic order. These observations are discussed in terms of the symmetry allowed magnetic interactions within and between the frustrated layers.

Publication types

  • Research Support, Non-U.S. Gov't