Magnetic dipole proton

Mclnnes EJL (2006) Spectroscopy of Single-Molecule Magnets. 122 69-102 Merunka D, Rakvin B (2007) Anharmonic and Quantum Effects in KDP-Type Ferroelectrics Modified Strong Dipole-Proton Coupling Model. 124 149-198 Meshri DT, see Singh RP (2007) 125 35-83... 

Nuclear Overhauser effect—The nuclear Overhauser effect (NOE) occurs only between nuclei that share a dipole coupling, i.e., their nuclei are so close that their magnetic dipoles interact. Techniques that use NOE enhance spectra and allow spacial relationships of protons to be determined. 

The rotation of the molecule causes a magnetic dipole-dipole interaction between the protons in the molecule, which is a function of the distance r between the two dipoles. The relaxation rate, varies linearly with the rotation... 

Further evidence for this mechanism of spin-spin coupling in liquids is the fact that the coupling dies off as the number of chemical bonds separating the two nuclei increases. Moreover, the fact that couplings between trans protons in olefins are greater than between cis protons is incompatible with a direct interaction between the two nuclear magnetic dipoles. 

Calculate the magnitude of the magnetic dipole moment vectors of (a) the proton (b) the neutron. 

The earliest work employed the method of moments, and Fraissard et al (192) were the first to consider in detail the second moment of the proton NMR resonance in nonspinning solids. In general, when the line shape is determined solely by the I-I and I-S magnetic dipole-dipole interaction, the Van Vleck second moment, M2, is given by (193)... 

In recent months results given in Table 2 have been obtained for magnetic dipole moments of Sb, I and Xe proton rich isotopes at the DOLIS-COLD facility at Daresbury. Examples of the data are given in Fig. 4. The 117Sb result should be compared with the established value of 3.54 nm. 

Here is yet another bizarre result of quantum mechanics for you to ponder. The lx wavefunction for a hydrogen atom is unequal to zero at the origin. This means that there is a small, but nonzero probability that the electron is inside the proton. Calculation of this probability leads to the so-called hyperfine splitting —the magnetic dipoles on the proton and electron interact. This splitting is experimentally measurable. Transitions between the hyperfine levels in the lx state of hydrogen are induced by radiation at 1420.406 MHz. Since this frequency is determined by... 

FIGURE 3.1 Spinning charge on proton generates magnetic dipole. 

NMR spectroscopy has been applied to the determination of the mean residence time of adsorbed molecules in essentially two different ways, namely by proton magnetic relaxation studies and deuteron magnetic resonace line shape analysis. In the case of adsorbed molecules, proton magnetic relaxation is mainly determined by magnetic dipole interactions with protons of the same molecule (intramolecular proton-proton... 

Finally in this brief review of magnetic dipole transitions we look at the proton magnetic resonance spectrum of H2 in its J = 1 rotational level in this level the two proton spins are combined to form a total spin / = 1 (this is ortho-H2). An applied static magnetic field defines the space-fixed p = 0 direction, the effective Hamiltonian being... 

The magnetic resonance spectrum of HF was studied some nine years earlier than the electric resonance spectrum by Baker, Nelson, Leavitt and Ramsey [93] in this case the transitions studied were magnetic dipole, corresponding to reorientation of the proton and fluorine nuclear spins. Values of the nuclear spin rotation and dipolar constants were essentially confirmed by the later electric resonance measurements. We now describe measurements of the electric resonance spectrum in the additional presence of a strong magnetic field, carried out by de Leeuw and Dymanus [89]. 

The NOE interaction between two proton magnetic dipoles takes place predominantly directly through space rather than through bonds (as is the case in normal spin coupling). This through-space interaction is very sensitive to the distance... 

An extensive solid-state cp/mas study was undertaken to determine 7) time-constants of 13C nuclei in the crystalline methochloride salt (22), and the results are reported in Fig. 6.29 Local magnetic fields from the two sets of rapidly rotating methyl proton magnetic dipoles (estimated to revolve at ca. 109 rotations/s in the solid)34 provide a distance-dependent relaxation mechanism for the neighboring... 

---