Multiple orbital effects and magnetic ordering in a neutral radical

Aaron Mailman; Stephen M Winter; Joanne W L Wong; Craig M Robertson; Abdeljalil Assoud; Paul A Dube; Richard T Oakley

doi:10.1021/ja512235h

Multiple orbital effects and magnetic ordering in a neutral radical

J Am Chem Soc. 2015 Jan 28;137(3):1044-7. doi: 10.1021/ja512235h. Epub 2015 Jan 14.

Authors

Aaron Mailman¹, Stephen M Winter, Joanne W L Wong, Craig M Robertson, Abdeljalil Assoud, Paul A Dube, Richard T Oakley

Affiliation

¹ Department of Chemistry, University of Waterloo , Waterloo, Ontario N2L 3G1, Canada.

PMID: 25588146
DOI: 10.1021/ja512235h

Abstract

The alternating ABABAB π-stacked architecture of the EtCN solvate of the iodo-substituted, oxobenzene-bridged bisdithiazolyl radical IBBO (space group Pnma) gives rise to strong ferromagnetic exchange along the π-stacks, and the material orders as a spin-canted antiferromagnet with T(N) = 35 K, with a spontaneous (canted) moment M(spont) = 1.4 × 10(-3) μB and a coercive field H(c) = 1060 Oe (at 2 K). The observation of spin-canting can only be understood in terms of multiorbital contributions to both isotropic and anisotropic exchange interactions, the magnitude of which are enhanced by spin-orbit effects arising from the heavy-atom iodine substituent. Pseudodipolar interactions lead to a net canted moment along the c-axis, while the sublattice magnetization is predicted to possess an easy a-axis.