Preparation and characterization of [Gd(hfac)3(DTBN)(H2O)] (DTBN = di-t-butyl nitroxide). Ferromagnetic Gd3+–Gd3+ super–superexchange

Abstract

The intramolecular radical–Gd antiferromagnetic coupling (2J₁/k_B = −11.6 K) is notably strong, as expected from our molecular design, and the intermolecular exchange coupling along the Gd–O–H⋯O–Gd bridges is unexpectedly ferromagnetic with the largest Gd⋯Gd coupling ever known (2J₂/k_B = +0.12 K).