Molecular qubits based on potentially nuclear-spin-free nickel ionsElectronic supplementary information (ESI) available: Details on synthesis and characterization of the compounds as well as methods and additional pulsed EPR data. See DOI: 10.1039/c6cp08161d

• Main Authors: Bader, K, Schlindwein, S. H, Gudat, D, van Slageren, J
• Format: Article
• Language: English
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c6cp08161d

Molecular qubits with the longest coherence times thus far are based on nuclear-spin-carrying central ions. These nuclear spins can cause quantum state leakage, which is detrimental to quantum algorithm performance. We present two novel molecular qubits based on potentially nuclear spin-free Ni in the formal oxidation state 3+. (d 20 -PPh 4 )[Ni(mnt) 2 ] ( Ni-mnt , mnt 2− = maleonitrile-1,2-dithiolate) possesses a coherence time of up to 38.7 μs at 7 K. Functionalization of the dithiolate ligand decreases the coherence time by a factor of only four in (HNEt 3 )[Ni(dip) 2 ] ( Ni-dip , dip 2− = 3-(diphenylphosphoryl)-methylbenzene-1,2-dithiolate), indicating that monoanionic Ni-dithiolene complexes are promising and robust building blocks for polynuclear molecular qubit gates. Molecular quantum bits based on potentially nuclear-spin-free nickel display coherence times of up to 40 microseconds.