Paramagnetic solvent effect

In Table 1-1 we thus report the N nuclear shielding (with its paramagnetic and diamagnetic contributions) and nitrogen lone pair natural population (NP(lp)) for the diazine showing the largest solvent effect, i.e., pyridazine, and its clusters in vacuo (VAC) and in the presence of an external PCM continuum. 

Compared with other metal nuclei, the Li chemical shift scale is rather small and the NMR signals of > Li encompass not more than ca 6 ppm for salt solutions and about 12 ppm for organolithium compounds. This can be attributed to the relatively small paramagnetic contribution to the shielding constant of Li which leads to a near cancellation of the diamagnetic term [46]. In addition, Li shifts are sensitive to solvent effects, viscosity. 

The term has previously been applied to the effect on chemical shift of specific solute—solvent interactions in solution, and it has been pointed out that these should cause a small paramagnetic solvent shift in this usage, shifts due to anisotropy effects associated with specific interactions are included in the term. In this discussion, however, we shall take to represent the effect of solvent anisotropy in a geometrically specific solute—solvent orientation which has been brought... 

Cr(acac)3 in various perdeuterated solvents, Nilenls in en Paramagnetic relaxation effects on nonexchanging systems 2000 298 H. N 141... 

EOM-CC), to projected coupled cluster theory with all single and double excitations (CCSD) ° As an additional requirements there are (e) the use of enough large basis sets with augmented basis functions to obtain reliable evalution of paramagnetic spin-orbit (PSO) and spin-dipole (SD) terms (f) the inclusion of vibrational corrections for the SSCC, and (g) the consideration of solvent effects on SSCCs. " The latter two requirements concern the comparison of calculated and measured SSCCs. 

When electronic paramagnetism originates from the coordination state of a metal atom, solvent effects may induce condiderable shifts when the ligand nucleophilicity is high. Thus, the cyanide resonance of N-enriched dicyanoprotohaemin complexes moves 250 ppm when passing from... 

The esr-spectroscopy is one of the most important techniques to detect and study photochemically excited (paramagnetic) triplet states of aromatic molecules or of molecules of biological interest. By his technique, very small changes in the electron distribution caused by inter- and intramolecular interactions (e.g. substitution effects, solvent effects, complex formation) may be detected [69]. 

Actually, our mixed discrete-continuum model is not limited to the study of UV-vis spectra, but it has been already successfully employed to model solvent effects on several different spectral properties, such as electron paramagnetic resonance (EPR) hyperfine coupling constants, nuclear magnetic resonance (NMR) chemical shifts, and so on [45, 121]. 

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