The substitution of one metal ion in a Cr-based molecular ring with dominant antiferromagnetic couplings allows the engineering of its level structure and ground-state degeneracy. Here we characterize a ${\mathrm{Cr}}_7\mathrm{Ni}$ molecular ring by means of low-temperature specific-heat and torque-magnetometry measurements, thus determining the microscopic parameters of the corresponding spin Hamiltonian. The energy spectrum and the suppression of the leakage-inducing $S$ mixing render the ${\mathrm{Cr}}_7\mathrm{Ni}$ molecule a suitable candidate for the qubit implementation, as further substantiated by our quantum-gate simulations.

The use of derivatised salicylaldoximes in Mn chemistry has led to the isolation of a plethora of beautiful new SMMs ranging in nuclearity from three to eight and with spin ground states as large as S = 12–including a Mn₆ complex with the largest energy barrier to magnetisation reversal yet reported. The deliberate chemically-induced structural distortion of the [Mn₆] molecule allows the isolation of analogous family members displaying remarkably different magnetic properties and this in turn allows for a rare semi-quantitative magneto-structural correlation which enables prediction of the magnetic properties of new family members.