Chemical Engineering of Molecular Qubits

We show that the electron spin phase memory time, the most important property of a molecular nanomagnet from the perspective of quantum information processing, can be improved dramatically by chemically engineering the molecular structure to optimize the environment of the spin. We vary systematically each structural component of the class of antiferromagnetic Cr7Ni rings to identify the sources of decoherence. The optimal structure exhibits a phase memory time exceeding 15 mu s.