One-dimensional clusters of 16-doxyl-stearate radicals in organic nanochannels as studied by electron paramagnetic resonance (EPR)

In this paper we report a variable temperature EPR investigation on auto-assembling inclusion compounds of tris(o-phenylenedioxy)cyclotriphosphazene (TPP), the nitroxide radical methyl ester of the 16-doxyl-stearic acid (16-dox), and diamagnetic co-guests of various polarities. By playing with the nature of the co-guest and the concentration of the radical we obtained radicals isolated, or in 1D clusters. Local order, dynamics and orientation of the guests have been obtained by simulations of the spectra of spin-carrying guests envisaged as probes. For the simulations, intra-channel and inter-channel radical pairs and trimers magnetic interactions have been modellized. The interest of similar compounds for 1D magnetic materials is discussed.

Graphical abstractInclusion compounds of the nitroxide radical 16-doxyl-sterate and diamagnetic co-guests in cyclophosphazene (TPP) channels have been studied by cw-EPR. The local order of the radicals depends on the nature of the co-guest. With apolar co-guests the radicals form mono-dimensional clusters.Figure optionsDownload full-size imageDownload as PowerPoint slide