Chiral molecular 4f qubits by post functionalization

We herein demonstrate the synthesis of a pair of enantiomerically pure Yb^III complexes by post-functionalisation of the parent Yb^III complex <i>via</i> condensation with an enantiomerically pure chiral amine. The enantiomeric pair is structurally characterised by single crystal and powder X-ray diffraction, showing that it crystalises in the <i>P</i>2₁2₁2₁ Sohncke space group with Flack parameters close to zero, which confirms their enantiopurity. Circular Dichroism (CD) and absorption spectroscopies in the NIR reveal sharp ²F_7/2 → ²F_5/2 f-f transitions, with <i>g</i> _abs values up to 0.07, indicating a chiral environment for the ytterbium centre. Furthermore, a dynamic mechanism with mixing of ligand states is shown to contribute to the CD intensity. X-band pulse Electron Paramagnetic Resonance spectroscopy, on a magnetically dilute single crystal containing 1% of Yb^III complexes within the isostructural Y^III diamagnetic host, reveals a phase memory time, <i>T</i> _m, of the electronic spin of 600 ns and that it can be coherently manipulated by microwave pulses, as evidenced by Rabi nutations.