@article {1398,
	title = {Optimization, standardization, and testing of a new NMR method for the determination of zeolite host-organic guest crystal structures},
	journal = {Journal of the American Chemical Society},
	volume = {128},
	number = {36},
	year = {2006},
	note = {ISI Document Delivery No.: 081BJTimes Cited: 15Cited Reference Count: 42Fyfe, Colin A. Brouwer, Darren H.},
	month = {Sep},
	pages = {11860-11871},
	type = {Article},
	abstract = {An optimized and automated protocol for determining the location of guest sorbate molecules in highly siliceous zeolites from Si-29 INADEQUATE and H-1/Si-29 cross polarization (CP) magic-angle spinning (MAS) NMR experiments is described. With the peaks in the Si-29 MAS NMR spectrum assigned to the unique Si sites in the zeolite framework by a 2D(29)Si INADEQUATE experiment, the location of the sorbate molecule is found by systematically searching for sorbate locations for which the measured rates of H-1/Si-29 cross polarization of the different Si sites correlate linearly with H-1/Si-29 second moments calculated from H-Si distances. Due to the H-1/Si-29 cross polarization being in the "slow CP regime" for many zeolite-sorbate complexes, it is proposed that the CP rate constants are best measured by H-1/Si-29 cross polarization drain experiments, if possible, to avoid complications that may arise from fast H-1 and Si-29 T-1 rho relaxations. An algorithm for determining the sorbate molecule location is described in detail. A number of ways to effectively summarize and display the large number of solutions which typically result from a prediction of the structure from the CP MAS NMR data are presented, including estimates of the errors involved in the structure determinations. As a working example throughout this paper, the structure of the low loaded rho-dichlorobenzene/ZSM-5 complex is determined under different conditions from solid-state H-1/Si-29 CP MAS NMR data, and the solutions are shown to be in excellent agreement with the known single-crystal X-ray diffraction structure. This structure determination approach is shown to be quite insensitive to the use of relative rate constants rather than absolute values, to the detailed structure of the zeolite framework, and relatively insensitive to temperature and motions.},
	keywords = {2ND MOMENT, CROSS-POLARIZATION, DETERMINATIONS, DISTANCE, H-ZSM-5, P-DICHLOROBENZENE, SINGLE-CRYSTAL, SOLID-STATE, SORBATE, SPINNING NMR, ZSM-5},
	isbn = {0002-7863},
	url = {<Go to ISI>://000240291900035},
	author = {Fyfe, C. A. and Brouwer, D. H.}
}
@article {5080,
	title = {Location of the fluoride ion in tetrapropylammonium fluoride silicalite-1 determined by H-1/F-19/Si-29 triple resonance CP, REDOR, and TEDOR NMR experiments},
	journal = {Journal of the American Chemical Society},
	volume = {123},
	number = {28},
	year = {2001},
	note = {ISI Document Delivery No.: 451LFTimes Cited: 48Cited Reference Count: 50},
	month = {Jul},
	pages = {6882-6891},
	type = {Article},
	abstract = {The location of the fluoride ion in tetrapropylammonium fluoride silicalite-1 ([TPA]-F-[Si-MFI]), an as-synthesized siliceous zeolite with the MEI topology, has been unambiguously determined using solid-state NMR experiments alone. With the H-1 {\textendash}> Si-29 CP-INADEQUATE experiment, the 12 peaks in the highly resolved Si-29 MAS NMR spectrum of [TPA]-F-[Si-MFI] were assigned. Using these peak assignments it was possible to perform H-1/F-19/Si-29 triple resonance CP, REDOR, and TEDOR experiments to measure F-Si distances and thus locate the fluoride ion. It is covalently bonded to Si-9 in the [4(1)5(2)6(2)] cage of the zeolite framework and exchanges between two "mirror-related" Si-9 sites, making them equivalent on the NMR time scale. The importance of this result and the general applicability of the approach are discussed.},
	keywords = {3-DIMENSIONAL BONDING CONNECTIVITIES, 5-COORDINATE, CONTAINING OCTADECASIL, CROSS-POLARIZATION NMR, CRYSTAL-STRUCTURE, DETERMINATIONS, DISTANCE, MAS-NMR, NATURAL-ABUNDANCE, PROTON-ENHANCED NMR, SILICON, SOLID-STATE SI-29},
	isbn = {0002-7863},
	url = {<Go to ISI>://000169803000018},
	author = {Fyfe, C. A. and Brouwer, D. H. and Lewis, A. R. and Chezeau, J. M.}
}
