title: Detection and characterization of intermolecular multiple-quantum coherence NMR signals of IS (I=1/2; S=3/2) spin systems.
abstract: Intermolecular multiple-quantum coherences (iMQCs) have some intrinsic properties different from conventional single-quantum coherences in solution NMR. In this paper, we extended our study to heteronuclear iMQCs in IS (I=1/2, S=3/2) spin systems. A sample of sodium chloride (NaCl) water solution was taken as an example. Heteronuclear COSY revamped by asymmetric Z-gradient echo detection (CRAZED) experiments were performed. One- and two-dimensional heteronuclear iMQC spectra were obtained. The quantum-mechanical treatment was used to deduce the signal expressions. Magic angle experiments validate that the signals are indeed from intermolecular dipolar interaction and insensitive to the imperfection of radio-frequency (RF) flip angles. Both experimental results and theoretical analysis indicate that heteronuclear CRAZED experiment allows coherence transfer from spin-3/2 nuclei to spin-1/2, and vice verse. Furthermore, the dependences of iMQC signal intensities on RF pulse flip angles follow the same rules as those for heteronuclear IS (I=1/2, S=1/2 or 1) spin systems.
authors.affiliation: Department of Physics, Fujian Key Laboratory of Plasma and Magnetic Resonance, State Key Laboratory of Physical Chemistry of Solid Surfaces, Xiamen University, Xiamen, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Zhang
authors.forename: Song
authors.initials: S
authors.lastname: Chen
authors.forename: Shuhui
authors.initials: S
authors.lastname: Cai
authors.forename: Zhong
authors.initials: Z
authors.lastname: Chen
mesh_terms: D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008433:Mathematics; D008962:Models, Theoretical; D011789:Quantum Theory; D012965:Sodium Chloride / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water; D012965:Sodium Chloride