@article {4951,
	title = {First observation of a residual inter-cationic correlation in the {\textquoteright}super{\textquoteright}-ionic conductor, Ag9GaSe6: Ag-109-Ag-107 double-resonance NMR study of ion dynamics},
	journal = {Solid State Ionics},
	volume = {132},
	number = {1-2},
	year = {2000},
	note = {ISI Document Delivery No.: 347GATimes Cited: 4Cited Reference Count: 37},
	month = {Jul},
	pages = {87-92},
	type = {Article},
	abstract = {A double-resonance nuclear magnetic resonance, NMR, signal between the very mobile nuclei of a superionic conductor has been detected for the first time in a silver conductor. The heteronuclear double-resonance signal between mobile nuclei should not be observed in the fast motion limit if the inter-cationic interactions are completely removed. However, a Ag-109-Ag-107 double-resonance signal has in fact been observed in a superionic conductor of 0.1-1 S m(-1), namely Ag9GaSe6. This implies that the cationic motion is correlated in this solid electrolyte and some residual interactions, perhaps including chemical bonds among very mobile cations, may remain even in the fast motion limit. (C) 2000 Elsevier Science B.V. All rights reserved.},
	keywords = {DIFFUSION, double resonance NMR, ECHO DOUBLE-RESONANCE, GLASSES, ion dynamics, MODEL, SILVER IONS, silver superionic conductor},
	isbn = {0167-2738},
	url = {<Go to ISI>://000088918700008},
	author = {Tansho, M. and Fyfe, C. A. and Grondey, H. and Markus, T. and Wada, H.}
}
@article {4815,
	title = {Investigation of the viability of solid-state NMR distance determinations in multiple spin systems of unknown structure},
	journal = {Journal of Physical Chemistry B},
	volume = {104},
	number = {1},
	year = {2000},
	note = {ISI Document Delivery No.: 283BJTimes Cited: 26Cited Reference Count: 37},
	month = {Jan},
	pages = {48-55},
	type = {Article},
	abstract = {This paper presents theoretical rotational-echo double-resonance (REDOR) and transferred-echo double-resonance (TEDOR) curves calculated for several three-spin systems and explores the potential for determining reliable distances in multiple-spin systems of unknown geometry. These NMR techniques can provide distances which compare very well with those obtained by X-ray diffraction if the samples contain isolated heteronuclear (IS) spin pairs and are currently being used in structural investigations of solids including peptides, polymers, and inorganic materials. The situation is less clear when small clusters of spins (e.g., INS systems) are present, and although the multispin dephasing can be calculated, very few examples have been reported in the literature. In most cases the spin system geometry was known before analysis of the NMR data, thus it is unclear whether reliable distances can be determined when the geometry of the spin system is completely unknown. To investigate the uniqueness of distance determinations from fitting of multispin REDOR and TEDOR data, the theoretical dephasing was calculated for a selection of I2S systems. The effects of varying the two I-S dipolar couplings and the I-A-S-I-B angle, zeta, were studied. The full range of zeta (0 degrees less than or equal to zeta less than or equal to 180 degrees) was considered, and the magnitudes of the dipolar couplings selected are typical of couplings expected for commonly studied nuclei. A variation of 10 degrees or more is required to effect a noticeable change and the dephasing is identical for zeta and 180 degrees - zeta. The most distinctive behavior is observed when zeta is small (or close to 180 degrees), otherwise there are quite minor differences. Spin systems with quite different geometries may exhibit very similar dephasing, and in some cases the curves are identical to those for an isolated IS spin pair. These calculations indicate that it is highly unlikely that reliable distances can be obtained directly from REDOR and TEDOR experiments on multiple spin systems when the number of spins and their geometrical arrangement is completely unknown. Furthermore, it is possible to obtain incorrect distances if isolated spin pairs are assumed and multiple spins are present.},
	keywords = {COMPLEX, DOUBLE-RESONANCE NMR, ECHO DOUBLE-RESONANCE, NMR, NUCLEI, QUADRUPOLAR, REDOR, ROTATIONAL-ECHO, zeolites},
	isbn = {1089-5647},
	url = {<Go to ISI>://000085256000007},
	author = {Fyfe, C. A. and Lewis, A. R.}
}
@article {3339,
	title = {DIPOLAR-BASED AL-27-]SI-29 SOLID-STATE NMR CONNECTIVITY EXPERIMENTS IN ZEOLITE MOLECULAR-SIEVE FRAMEWORKS},
	journal = {Journal of Physical Chemistry},
	volume = {99},
	number = {21},
	year = {1995},
	note = {ISI Document Delivery No.: RA147Times Cited: 64Cited Reference Count: 38},
	month = {May},
	pages = {8707-8716},
	type = {Article},
	abstract = {In this work we present the results of a systematic investigation of a set of dipolar-based Al-27 {\textendash}> Si-29 connectivity experiments for a series: of representative zeolite molecular sieve frameworks: zeolites A, X, Y, and Omega. Coherence transfer from quadrupolar Al-27 (I = 5/2) to Si-29 (I = 1/2) nuclei through cross polarization and transferred-echo double-resonance (TEDOR) experiments is. observed, and an experimental investigation of the parameters controlling the efficiency of both experiments is presented. Rotational-echo double-resonance (REDOR) and dipolar-dephasing difference experiments are also demonstrated. These experiments utilize the heteronuclear dipolar couplings, whose magnitudes are proportional to the inverse third power of the internuclear distance and are therefore extremely sensitive to the separation of the coupled spins. In addition, we demonstrate that for these dipolar-based experiments, there is a relative enhancement of a given resonance which is approximately linear with the number of aluminum atoms in the neighboring tetrahedral sites. Two-dimensional extensions of the cross-polarization and TEDOR experiments are also possible and will be of use for complex mixtures or where several resonances are observable in the one-dimensional spectra of the two nuclei.},
	keywords = {ANGLE, CROSS-POLARIZATION, DOUBLE-ROTOR, ECHO DOUBLE-RESONANCE, INORGANIC SOLIDS, MAS-NMR, NMR, NUCLEAR MAGNETIC-RESONANCE, QUADRUPOLAR NUCLEI, SPECTROSCOPY, VPI-5},
	isbn = {0022-3654},
	url = {<Go to ISI>://A1995RA14700041},
	author = {Fyfe, C. A. and Wongmoon, K. C. and Huang, Y. and Grondey, H. and Mueller, K. T.}
}
@article {7238,
	title = {COHERENCE TRANSFER INVOLVING QUADRUPOLAR NUCLEI IN SOLIDS - AL-27-REVERSIBLE-ARROW-P-31 CROSS-POLARIZATION NMR IN THE MOLECULAR-SIEVE VPI-5},
	journal = {Journal of the American Chemical Society},
	volume = {114},
	number = {14},
	year = {1992},
	note = {ISI Document Delivery No.: JB980Times Cited: 57Cited Reference Count: 36},
	month = {Jul},
	pages = {5876-5878},
	type = {Note},
	keywords = {AL-27, ANGLE, ECHO DOUBLE-RESONANCE, HIGH-RESOLUTION NMR, MAGIC, MAGNETIC-RESONANCE, PROTON, SPECTROSCOPY},
	isbn = {0002-7863},
	url = {<Go to ISI>://A1992JB98000069},
	author = {Fyfe, C. A. and Grondey, H. and Mueller, K. T. and Wongmoon, K. C. and Markus, T.}
}
