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Quadrupolar

Bhowmik P K and Su T 1986 Tra]ectory calculations of ion-quadrupolar molecule collision rate constants J. Chem. Phys. 84 1432-4... [Pg.824]

B1.12.4.5 HIGH-RESOLUTION SPECTRA FROM QUADRUPOLAR NUCLEI... [Pg.1484]

Intramolecular quadrupolar 2 Reorientation of the electric field gradient principal axis Dominant for />1 (covalently bonded) [14]... [Pg.1506]

Intermolecular quadrupolar 2 Fluctuation of the electric field gradient, moving multipoles Common for />1 In free Ions In solution [la... [Pg.1506]

Huntress WT 1970 The study of anisotropic rotation of molecules in liquids by NMR quadrupolar relaxation Adv. Magn. Reson. 4 1-37... [Pg.1516]

Werbelow L G 1996 Relaxation theory for quadrupolar nuclei Encyclopedia of Nuclear Magnetic Resonance ed D M Grant and R K Harris (Chichester Wiley) pp 4092-101... [Pg.1516]

Roberts J E and Schnitker J 1993 Ionic quadrupolar relaxation in aqueous solution—dynamics of the hydration sphered. Rhys. Chem. 97 5410-17... [Pg.1516]

Champmartin D and Rubini P 1996 Determination of the 0-17 quadrupolar coupling constant and of the C-13 chemical shielding tensor anisotropy of the CO groups of pentane-2,4-dione and beta-diketonate complexes in solution. NMR relaxation study/norg. Chem. 35 179-83... [Pg.1518]

Amphiphiles often have a complex phase behaviour with several liquid crystalline phases These liquid crystalline phases are often characterised by long-range order in one directior together with the formation of a layer structure. The molecules may nevertheless be able tc move laterally within the layer and perpendicular to the surface of the layer. Structura information can be obtained using spectroscopic techniques including X-ray and neutror diffraction and NMR. The quadrupolar splitting in the deuterium NMR spectrum can be... [Pg.411]

Unlike simple deflections or accelerations of ions in magnetic and electric fields (Chapter 25), the trajectory of an ion in a quadrupolar field is complex, and the equations of motion are less easy to understand. Accordingly, a simplified version of the equations is given here, with a fuller discussion in the Appendix at the end of this chapter. [Pg.183]

Relationship between a and q. The shaded area indicates regions of stable ion motion through the quadrupolar field. [Pg.187]

The signal from H(3) is broadened because N-H(3) spin coupling is not completely washed out by quadrupolar relaxation of the nitrogen atom (68MI41701>. This broadening niay be useful in assigning signals in the spectrum and it is usually reduced in solvents of... [Pg.136]

This compound has two crystallographically distinct vanadium sites. While the static spectrum is a superposition of two powder patterns of the kind shown in Figure 3, MAS leads to well-resolved sharp resonances. Weak peaks denoted by asterisks are spinning sidebands due to the quadrupolar interaction. [Pg.468]

The moment of inertia 1 determines the rotational constant 0 = h /IT, which is the parameter that controls the strength of quantum effects. The other parameter of the model, which is the quadrupolar coupling constant K, can be conveniently taken as the energy and temperature scale. We can thus reduce all quantities related to energies by K, and define, e.g., the dimensionless temperature = k T/K, energy = E/K, and rotational... [Pg.113]

One prominent example of rods with a soft interaction is Gay-Berne particles. Recently, elastic properties were calculated [89,90]. Using the classical Car-Parrinello scheme, the interactions between charged rods have been considered [91]. Concerning phase transitions, the sohd-fluid equihbria for hard dumbbells that interact additionally with a quadrupolar force was considered [92], as was the nematic-isotropic transition in a fluid of dipolar hard spherocylinders [93]. The influence of an additional attraction on the phase behavior of hard spherocylinders was considered by Bolhuis et al. [94]. The gelation transition typical for clays was found in a system of infinitely thin disks carrying point quadrupoles [95,96]. In confined hquid-crystalline films tilted molecular layers form near each wall [97]. Chakrabarti has found simulation evidence of critical behavior of the isotropic-nematic phase transition in a porous medium [98]. [Pg.764]

The only sulfur isotope with a nuclear spin is which is quadrupolar (/ = 3/2) and of low natural abundance (0.76%). In view of these inherent difficulties and the low symmetry around the sulfur nuclei in most S-N compounds, S NMR spectroscopy has found very limited application in S-N chemistry. However, it is likely that reasonably narrow resonances could be obtained for sulfur in a tetrahedral environment, e.g. [S(N Bu)4], cf. [S04] . On the other hand both selenium and tellurium have isotopes with I = Vi with significant natural abundances ( Se, 7.6% and Te, 7.0%). Consequently, NMR studies using these nuclei can provide useful information for Se-N and Te-N systems. [Pg.35]

There is arbitr iriness in describing phenomena as either physical or chemical, but in some sense the nuclear relaxation mechanisms we have discussed to this point are physical mechanisms, based as they are on rotational motions of molecules, magnetic dipole-dipole interactions, quadrupolar interactions, and so on. Now we discuss a nuclear relaxation mechanism that is chemical in origin. [Pg.166]

In Eq. (8-7), which is Coulomb s law, the charges are to be aeeompanied with their signs. Because of the high-order reciprocal dependence on distance in Eqs. (8-11) and (8-12), these quadrupolar interactions are usually negligible. For uncharged polar molecules the dipole-dipole interaction of Eq. (8-10), which has the dependence, is the most important contributor to the electrostatie potential energy. [Pg.392]

The isotope has a nuclear spin quantum number I and so is potentially useful in nmr experiments (receptivity to nmr detection 17 X 10 that of the proton). The resonance was first observed in 1951 but the low natural abundance i>i S(0.75%) and the quadrupolar broadening of many of the signals has so far restricted the amount of chemically significant work appearing on this rcsonance, However, more results are expected now that pulsed fourier-transform techniques have become generally available. [Pg.662]

Once an approximation to the wavefunction of a molecule has been found, it can be used to calculate the probable result of many physical measurements and hence to predict properties such as a molecular hexadecapole moment or the electric field gradient at a quadrupolar nucleus. For many workers in the field, this is the primary objective for performing quantum-mechanical calculations. But from... [Pg.103]

A spherical object cannot radiate gravitational waves (quadrupolar source term). [Pg.313]


See other pages where Quadrupolar is mentioned: [Pg.1467]    [Pg.1514]    [Pg.1514]    [Pg.80]    [Pg.164]    [Pg.185]    [Pg.415]    [Pg.18]    [Pg.139]    [Pg.470]    [Pg.82]    [Pg.110]    [Pg.118]    [Pg.119]    [Pg.120]    [Pg.359]    [Pg.605]    [Pg.802]    [Pg.802]    [Pg.803]    [Pg.191]    [Pg.409]    [Pg.72]    [Pg.2]    [Pg.221]    [Pg.221]    [Pg.9]    [Pg.65]    [Pg.67]   
See also in sourсe #XX -- [ Pg.20 , Pg.106 ]

See also in sourсe #XX -- [ Pg.754 ]

See also in sourсe #XX -- [ Pg.754 ]

See also in sourсe #XX -- [ Pg.754 ]




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2H quadrupolar

Chemical shielding interactions, quadrupolar nuclei

Chemical shift anisotropy , quadrupolar nuclei

Chemical shift quadrupolar correlation

Chromophores quadrupolar

Coupling quadrupolar

Coupling to quadrupolar nuclei

Couplings anisotropic quadrupolar

Deuteration quadrupolar coupling

Deuterium quadrupolar echo

Deuterium quadrupolar splitting

Deuteron quadrupolar splitting

Dyes quadrupolar

Echo, quadrupolar

Effective quadrupolar centres

Electric quadrupolar interaction

Electric-field-gradient tensor quadrupolar coupling constant

Electric-field-gradient tensor quadrupolar interactions

Energy dipole-quadrupolar

Field quadrupolar

Flexoelectricity quadrupolar

Half second-order quadrupolar broadening

Half-integer quadrupolar nuclei

Half-integer spin quadrupolar nuclei

Hamiltonian quadrupolar

Homonuclear dipolar recoupling, quadrupolar

Intermolecular quadrupolar

Intermolecular quadrupolar relaxation

Kondo quadrupolar

Magic angle spinning technique second-order quadrupolar interaction

Magic angle with quadrupolar nuclei

Magnetic susceptibility quadrupolar

Mechanism quadrupolar

Metallic nuclei, quadrupolar

Multiple-quantum magic-angle spinning quadrupolar interaction

N Quadrupolar Relaxation

NMR of Quadrupolar Nuclei in Supercritical CO

NMR of quadrupolar nuclei

Nuclear electric quadrupolar interaction

Nuclear magnetic resonance quadrupolar interaction

Nuclear magnetic resonance spectroscopy quadrupolar interactions

Nuclear quadrupolar effects

Nuclear quadrupolar resonance

Oxygen-17 quadrupolar effects

Perturbation quadrupolar

Powder pattern first-order quadrupolar

Powder pattern second-order quadrupolar

Pseudo-quadrupolar interaction

Pseudo-quadrupolar transitions

Quadrupolar 300 INDEX

Quadrupolar Carr-Purcell -Meiboom - Gill QCPMG) pulse sequence

Quadrupolar Carr-Purcell Meiboom-Gill pulse sequence

Quadrupolar Carr-Purcell-Meiboom-Gill

Quadrupolar Carr-Purcell-Meiboom-Gill QCPMG)

Quadrupolar Carr-Purcell-Meiboom-Gill QCPMG) experiment

Quadrupolar Hamiltonian coupling

Quadrupolar Nucleus Experiments

Quadrupolar Pake pattern

Quadrupolar alignment

Quadrupolar asymmetry parameter

Quadrupolar axially symmetric

Quadrupolar bond with

Quadrupolar broadening

Quadrupolar broadening nuclei

Quadrupolar broadening relaxation

Quadrupolar cobalt

Quadrupolar couphng constants

Quadrupolar coupling constants

Quadrupolar coupling electric field gradient

Quadrupolar definition

Quadrupolar echo modulation

Quadrupolar echo pulse sequence

Quadrupolar echo sequence

Quadrupolar effects

Quadrupolar excitation

Quadrupolar forces

Quadrupolar frequency

Quadrupolar from spin-lattice relaxation times

Quadrupolar halogen nuclei

Quadrupolar hydrated cations

Quadrupolar intensities

Quadrupolar interaction description

Quadrupolar interaction dominates central transition

Quadrupolar interaction nuclear spin energy levels

Quadrupolar interaction nucleus

Quadrupolar interaction second-order

Quadrupolar interaction second-order perturbation theory

Quadrupolar interaction treatment

Quadrupolar interactions

Quadrupolar interactions asymmetry parameter

Quadrupolar interactions relaxation mechanisms

Quadrupolar line shapes

Quadrupolar line-broadening

Quadrupolar lineshape

Quadrupolar lineshape analysis

Quadrupolar lineshape analysis - 2H NMR

Quadrupolar magnetic field

Quadrupolar magnetically induced nuclear interaction

Quadrupolar metals

Quadrupolar molecules

Quadrupolar moment

Quadrupolar momentum

Quadrupolar nuclear broadening

Quadrupolar nuclear electric quadrupole moment

Quadrupolar nuclear splitting

Quadrupolar nuclei

Quadrupolar nuclei frequency

Quadrupolar nuclei indirect determination

Quadrupolar nuclei isotropic signals

Quadrupolar nuclei line broadening effect

Quadrupolar nuclei linewidths

Quadrupolar nuclei observing

Quadrupolar nuclei parameters

Quadrupolar nuclei sensitivity

Quadrupolar nuclei theory

Quadrupolar nuclei, physics

Quadrupolar nuclei/coupling

Quadrupolar nucleus properties

Quadrupolar operator

Quadrupolar order

Quadrupolar ordering

Quadrupolar parameters

Quadrupolar pattern

Quadrupolar pattern chromophores

Quadrupolar pattern complexes

Quadrupolar polarizability

Quadrupolar polarization

Quadrupolar potential

Quadrupolar relaxation

Quadrupolar relaxation examples

Quadrupolar relaxation mechanism

Quadrupolar relaxation models

Quadrupolar relaxation rate

Quadrupolar resonance

Quadrupolar resonance spectroscopy

Quadrupolar solvents

Quadrupolar spectrometer

Quadrupolar spin relaxation

Quadrupolar spin theory

Quadrupolar spins

Quadrupolar splitting

Quadrupolar splitting constants

Quadrupolar splitting, Mossbauer spectra

Quadrupolar splittings

Quadrupolar tensors

Quadrupolar transitions

Quadrupolar, chemical shift anisotropy

Relaxation of quadrupolar nuclei

Residual Coupling Effects due to Quadrupolar Nuclei in MAS Spectra

Residual quadrupolar couplings

Residual quadrupolar interaction

Residual quadrupolar splitting, dependence

Special Considerations for MAS of Quadrupolar Nuclei

Spectral simulation, quadrupolar interactions

Static quadrupolar coupling constant

Static quadrupolar patterns

Subject quadrupolar

Symmetry quadrupolar lineshapes

Tensor quadrupolar coupling

Theory of Quadrupolar Spins Line Narrowing Techniques

Zeeman-quadrupolar Hamiltonian

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