A Complete Product Operator Theory for IS (I = 1, S = 1) Spin System and Application to 3D HMQC-COSY NMR Experiment

Abstract

There exist a variety of multi-pulse NMR experiments for spectral assignment of complex molecules in solution. The conventional heteronuclear multiple-qüantüm coherence (HMQC) NMR experiment provides correlation between weakly coupled hetero-nuclei. The COSY is one of the most popülar two-dimensional NMR experiment which is used to correlate J-coupled homo-nüclei of spectral assignment. The combination of the conventional HMQC and COSY NMR experiments yields a new experiment called 3D HMQC-COSY NMR experiment. The product operator theory is widely üsed for the analytical descriptions of multi-pulse NMR experiments for weakly coupled spin systems in liquuids. in this study, complete product operator theory for weakly coupled IS (I = 1, S = 1) spin system is presented by obtaining the evolütions of the prodüct operators ünder the spin-spin coupling Hamiltonian. As an application and a verification, analytical descriptions of 3D HMQC-COSY NMR experiment are obtained for weakly coupled IS<inf>n</inf>I'S'<inf>m</inf> (I = I’ = 1/2; S = S’ = 1; n = 1,2,3; m = 1,2) multi-spin systems. Then the estimated spectra of this experiment for various multi-spin systems are explained in detail. © 2014, Verlag der Zeitschrift für Naturforschung. All rights reserved.