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Terminal Ligand and Packing Effects on Slow Relaxation in an Isostructural Set of [Dy(H₂ dapp)X₂ ]⁺ Single Molecule Magnets*.

ABSTRACT: We report three structurally related single ion Dy compounds using the pentadentate ligand 2,6-bis((E)-1-(2-(pyridin-2-yl)-hydrazineylidene)ethyl)pyridine (H₂ dapp) [Dy(H₂ dapp)(NO₃ )₂ ]NO₃ (1), [Dy(H₂ dapp)(OAc)₂ ]Cl (2) and [Dy(H₂ dapp)(NO₃ )₂ ]Cl_0.92 (NO₃ )_0.08 (3). The (H₂ dapp) occupies a helical twisted pentagonal equatorial arrangement with two anionic ligands in the axial positions. Further influence on the electronic and magnetic structure is provided by a closely associated counterion interacting with the central N-H group of the (H₂ dapp). The slow relaxation of the magnetisation shows that the anionic acetates give the greatest slowing down of the magnetisation reversal. Further influence on the relaxation properties of compounds1 and 2 is the presence of short nitrate-nitrate intermolecular ligand contact opening further lattice relaxation pathways.

SUBMITTER: Pfleger RF

PROVIDER: S-EPMC8596592 | biostudies-literature |

REPOSITORIES: biostudies-literature

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