A chiral coordination polymer with double coaxially nested helical chains exhibiting spin-canting antiferromagnetism

Abstract

A chiral coordination polymer, fabricated by the rare alternate arrangement of two types of double coaxially nested helical chains, which spiral towards the parallel and inverse directions, exhibits spin-canting antiferromagnetism.Chiral coordination polymers have been paid remarkable attention in recent years, not only because of their fascinating architectures, but also for their tremendous value in enantioselective separations, nonlinear optics, asymmetric catalysis and magnetism, etc. 1 Many of the synthesized chiral coordination polymers have been found to possess beautiful helical structures, which are usually related to the occurrence of chirality. 2 Up to now, though a large number of helical coordination polymers holding single-, double-, triple-, and multiple-stranded helices have been obtained, 3 nested helical coordination polymers with the same helix axis are not common and only a few cases have been reported, 3d,4 which are constructed by encapsulation of the inner helices into the outer ones. As well, among the present cases, the inner and outer helices spiralling towards opposite directions are rare. Herein, with chiral D-camphoric acid IJD-H 2 ca) as a starting material, we have obtained a new coordination polymer ijNi 3 IJOH) 2 IJD-ca) 2 IJD-H 2 ca) 3 ] n (1), which is a chiral three-dimensional framework and exhibits spin-canting antiferromagnetism. ‡ To the best of our knowledge, Bu's group has done abundant research in the chirality field and synthesized many beautiful coordination polymers related to camphoric acid. 5 Even so, notably, compound 1 contains two types of double coaxially nested helical chains spiralling towards the parallel and CrystEngComm This journal is

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