Probing the Conformational Behavior of a Seven Hetero-Spin Supramolecule
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Updated: Oct 31, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
Lubomir Loci1,2, Tom S Bennett1, Selena J Lockyer1,2
1Department of Chemistry, The University of Manchester, Oxford Road, ManchesterM13 9PL, United Kingdom.
Abstract:
The synthesis and crystal structure of a 7-spin supramolecular poly-rotaxane is reported. The [4]rotaxane structure involves a trigonal thread centred on a {CrNi2} core, with each of the three arms terminated by Cu(II) centres and bearing a {Cr7Ni} metallocycle. The macromolecule brings together three distinct electron spin centers. Continuous-wave electron paramagnetic resonance spectroscopy confirms the molecule remains intact in solution, with the three types of spin center each uniquely addressable. Orientation-selective Double Electron Electron Resonance (DEER) and Relaxation Induced Dipolar Modulation Enhancement (RIDME) spectroscopies are used to selectively probe the different spin-spin interactions in the frozen solution phase and to define differences from the solid-state crystal structure.
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