Relaxation interactions

Under these conditions, and neglecting external relaxation-interactions according to Eq. 4, the pairwise relaxation-contributions, py, are evaluated from Eqs. 10-12, provided that an equal number of experimentally determined values are available. For a weakly coupled, three-spin system,... 

At this point, only one type of H% is considered. To account for possible interference effects or cross correlations among two different relaxation interactions X and V with ranks l and /, respectively, the above equation is modified to give39... 

Fig.l Cross-correlated relaxation Interaction between magnetic moments are dependent on the angle between them. This interaction is only present for large proteins or protein-ligand complexes... 

M13 M. Remko and L. Krasnek, Adv. Mol. Relaxation Interact. Processes 18, 1... 

Alfimova, E.Ya., and Likhtenshtein, G.I. (1979) Investigation of structure and conformational change of proteins by the inductive resonance energy transfer, Advans. Mol. Relax. Interact. Proc. 14, 47-89. 

On these systems the C longitudinal relaxation times T of the C5Me5 moieties have been measured by means of the Torchia s pulse sequence [48]. The Ti( C) values obtained for ring carbons have been rationalized on the basis of two relaxation interactions (dipole-dipole and chemical shift anisotropy) modulated by the motions involving the permethylated cyclopentadienyl rings. Interestingly, a qualitative comparison between solution and solid state C relaxation data shows that the same relaxation mechanisms are operative in both physical states. 

Anisotropy of the repulsive core or of the attractive well, or both, can be treated in a similar manner, and as a practical example we will consider V-T transfer for an intermolecular potential composed of a spherical repulsive core surrounded by an anisotropic attractive well (such as dipole-dijjole interaction). We will further invoke an approximate localization of the relaxation interaction on the repulsive core, implying that the multipolar long-range forces do not directly influence the relaxation probability. This assumption is... 

Keywords glass transition, stractural relaxation, frequency dispersion, secondary relaxation, many-body relaxation, interacting systems... 

Used mainly in anesthesia protocols or in the ICU to afford muscle relaxation and/or immobility. Occasionally used to treat tetanus. These muscle relaxants interact with nicotinic receptors at the skeletal muscle end plate. Nicotinic receptors are comprised of five subunits, two of which (alpha) bind ACh, a requirement for opening of the Na+ channel. Most drugs in this class bind competitively to one of the alpha subunits to prevent depolarization (receptor antagonists) one drug (succinylcholine) binds noncompetitively and opens the Na+ channel, causing excessive depolarization and desensitization. 

Muscle relaxants interact with nicotinic ACh receptors at the neuromuscular junction. Drugs ... 

The relaxed interaction energy idea may be extended still further by also allowing energy optimization within a subset of the R c coordinates. For example, one of the choices may allow optimization of the rotational degrees of freedom of each molecule (while still keeping other degrees of freedom in R jc fixed). 

This is similar to calculating the relaxed interaction energy of Eq. (13.2). 

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