title: Constants of motion in NMR spectroscopy.
abstract: We present a general method for constructing a subset of the constants of motion in terms of products of spin operators. These operators are then used to give insight into the multi-spin orders comprising the quasi-equilibrium state formed under a Jeener-Broekaert sequence in small, dipolar-coupled, spin systems. We further show that constants of motion that represent single-quantum coherences are present due to the symmetry of the dipolar Hamiltonian under 180 degrees spin rotations, and that such coherences contribute a DC component to the FID which vanishes in the absence of the flip-flop terms and is only present for spin clusters with an odd number of spins.
authors.affiliation: Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA. jwalls@fas.harvard.edu
authors.forename: Jamie D
authors.initials: JD
authors.lastname: Walls
authors.forename: Yung-Ya
authors.initials: YY
authors.lastname: Lin
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008956:Models, Chemical; D009038:Motion; D012399:Rotation; D013113:Spin Labels
chemical_list: D013113:Spin Labels