Abstract: A molecular-spin qubit is formed from a coordination complex having a plurality of strong-field ligands bound to a metal-atom center. The ground state has non-zero spin, and the resulting ground-state magnetic sublevels are separated by microwave or millimeter-wave frequencies, even in the absence of an external field. Two of these sublevels may be used as a quantum resource for quantum information processing, quantum communication, quantum memory, sensing, and other applications. Optical pumping to an excited state may be used to spin-polarize the molecular-spin qubit, and to measure its population by detecting photoluminescence. The energy-level structure of the metal-atom center can be modified due to its interaction with the ligands, therefore allowing the molecular-spin qubit to be “chemically tuned” based on the number and type of ligands. Ensembles of these molecular-spin qubits can be controllably deposited on a surface, or otherwise integrated into devices and structures.