title: Symmetry constraints on spin dynamics: Application to hyperpolarized NMR.
abstract: Spin dynamical evolution is constrained by the symmetries of the spin Hamiltonians that generate the quantum dynamics. The consequences of symmetry-induced constraints are examined for some common hyperpolarized NMR experiments, including the excitation of singlet order in spin-pair systems, and the transfer of parahydrogen-induced hyperpolarized singlet order to magnetization in systems displaying chemical and magnetic equivalence.
authors.affiliation: School of Chemistry, University of Southampton, University Road, SO17 1BJ Southampton, UK. Electronic address: mhl@soton.ac.uk.
authors.forename: Malcolm H
authors.initials: MH
authors.lastname: Levitt
keywords: Chemical equivalence; Long-lived states; Magnetic equivalence; Permutation symmetry; Spin dynamics; Unitary bounds