Guest-Adaptable Spin Crossover Properties in a Dinuclear Species Underpinned by Supramolecular Interactions

John E Clements; Peter R Airey; Florence Ragon; Vivian Shang; Cameron J Kepert; Suzanne M Neville

doi:10.1021/acs.inorgchem.8b02625

Guest-Adaptable Spin Crossover Properties in a Dinuclear Species Underpinned by Supramolecular Interactions

Inorg Chem. 2018 Dec 3;57(23):14930-14938. doi: 10.1021/acs.inorgchem.8b02625. Epub 2018 Nov 20.

Authors

John E Clements¹, Peter R Airey¹, Florence Ragon¹, Vivian Shang¹, Cameron J Kepert¹, Suzanne M Neville²

Affiliations

¹ School of Chemistry , The University of Sydney , Sydney , New South Wales 2006 , Australia.
² School of Chemistry , The University of New South Wales , Sydney , New South Wales 2052 , Australia.

PMID: 30457851
DOI: 10.1021/acs.inorgchem.8b02625

Abstract

Molecular crystals with guest-adaptable crystalline structures and properties are comparatively rare owing to their inherent reduced structural stability and malleability to support molecular variation. To overcome this intrinsic challenge, here we introduce structural stabilizing supramolecular interactions into a dinuclear material and henceforth demonstrate a dynamic structural and spin crossover property interchange between solvated (A·3MeOH) and desolvated (A·Ø) products (A = [Fe^II₂( o-NTrz)₅(NCS)₄]; 4-( o-nitrobenzyl)imino-1,2,4-triazole). Relatively uncommon for molecular species, the guest molecules in A·3MeOH are evolved (A·Ø) via a single-crystal to single-crystal transformation with affiliated phase transition resulting in a reversible transformation from one- to two-step spin crossover (SCO) transition character. We additionally present the water-saturated product (A·3H₂O), which distinctly shows an abrupt one-step SCO character with a 22 K wide thermal hysteresis loop. Detailed structure-property analysis highlights that the substantial structural malleability and guest-adaptable SCO properties of this dinuclear species are afforded by the supportive, yet flexible, supramolecular interaction pathways derived from the ligand functionalization.