1. Contribution from the Oxford Centre for Molecular Sciences, University of Oxford, Central Chemistry Laboratory, South Parks Road, Oxford, OX1 3QH, United Kingdom, Oxford Centre for Molecular Sciences, University of Oxford, Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford, OX1 3QZ, United Kingdom, Centre for Quantum Computation, Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom, University Chemical Laboratory, University of...