Hu J Z, Pugmire R J, Orendt A M, Grant D M, Ye C
Department of Chemistry, University of Utah, Salt Lake City 84112.
Solid State Nucl Magn Reson. 1992 Nov;1(4):185-95. doi: 10.1016/s0926-2040(10)80003-7.
Taking advantage of the long 13C T1 values generally encountered in solids, selective saturation and inversion of more than one resonance in 13C CP/MAS experiments can be achieved by sequentially applying several DANTE pulse sequences centered at different transmitter frequency offsets. A new selective saturation pulse sequence is introduced composed of a series of 90 degrees DANTE sequences separated by interrupted decoupling periods during which the selected resonance is destroyed. Applications of this method, including the simplification of the measurement of the principal values of the 13C chemical shift tensor under slow MAS conditions, are described. The determination of the aromaticity of coal using a relatively slow MAS rate is also described.
