Sulfur-33 magnetic resonance spectra of selected compounds

Abstract

Sulfur-33, because of its low natural abundance, spin of 3/2, and large quadrupole moment, has been a much neglected nucleus in nmr as well as in other branches of spectroscopy. The use of high rf power levels incident upon the sample, large modulation amplitudes, and signal averaging, however, permits nmr spectra with reasonable signal/noise ratios to be obtained. The present 33S nmr investigation was undertaken to explore the potential of the technique as a structure-determining tool. 33S chemical shifts and spectral line widths are presented for 12 materials. The range of chemical shifts is nearly 600 ppm, whereas spectral line widths vary from ~0 . 2 to 16 G . The organic compounds investigated were carbon disulfide, dimethyl sulfoxide, ethyl disulfide, tetrahydrothiophene, thiophene, and three substituted thiophenes. The inorganic compounds examined included concentrated and dilute (10 N) sulfuric acid, aqueous sodium sulfide, and the sulfide anion in cubic zinc sulfide. The highest field resonances were observed for aqueous sodium sulfide and for S2-; the lowest field resonance was for 10 N sulfuric acid. The effects of high symmetry about sulfur and fast chemical exchange on 33S spectral line widths are discussed and illustrated. The 33S nmr results are compared with those of other nuclei in chemically similar compounds.ulfur-33, the only reasonably abundant sulfur iso-

NMR Study of the Zinc Chalcogenides (ZnX, X = O, S, Se, Te)

“…The dipoles can be calculated from given values of electronic polarizability and equations of self-consistent field, and we investigate the resulting field and field gradient a t the two at0rn.c sites [ l l , 121. Because of axial site symmetry, the field and its principal gradient lie in the Structural parameters (c/a, u ) of wurtzite.zero local field at both atomic sites; --zero field gradient at both sites due to monopoles; --------equal nearestneighbour distances; @ the ideal point; 0 parameters of (1) AlN, (2) ZnO, (3) BeO, (4) CdS, (5) CdSe, ( 6 ) AgI ([l]); o parameters of ZnS (predicted) c/az-direction. Since each sublattice is h.c.p., the field due t o monopoles and the field gradient due to dipoles vanish a t field points on the same sublattice as the source.…”

Multinuclear magnetic resonance studies of 2‐aryl‐1,3,4‐thiadiazoles

“…Because the observed substituent‐induced shifts were less than the accuracy of measurement, the spectra of the other compounds were not recorded. The value obtained is similar to that reported for thiophenes (−112 ppm for 2‐methylthiophene) or 2‐methylthiazol (−72 ppm) …”

“…The value obtained is similar to that reported for thiophenes (À112 ppm for 2-methylthiophene) or 2-methylthiazol (À72 ppm). [55,56]…”

A high-resolution natural abundance 33S MAS NMR study of the cementitious mineral ettringite

“…The earliest solid-state 33 S NMR studies date back to 1968 and the immediately ensuing investigations were performed exclusively on sulfides. [2][3][4][5][6]8 In 1986, Eckert and Yesinowski 7 reported an extensive study of ''static'' solid-state 33 S NMR spectra recorded at B 0 = 11.7 T from a total of 27 inorganic compounds including sulfides, sulfates and alums. The first 33 S MAS NMR spectra were reported in 1996.…”