A series of four anhydrous group 13 chloride salts has been studied by (35/37)Cl solid-state NMR spectroscopy and complementary quantum chemical calculations. Due to the large (35/37)Cl quadrupolar interactions in these salts, a high magnetic field (21.1 T) and the variable-offset QCPMG technique was used to obtain full chlorine central transition (m = -1/2 <--> 1/2) NMR spectra. Analyses of th...

In 2001, Mauri and Pickard introduced the gauge including projected augmented wave (GIPAW) method that enabled for the first time the calculation of all-electron NMR parameters in solids, i.e. accounting for periodic boundary conditions. The GIPAW method roots in the plane wave pseudopotential formalism of the density functional theory (DFT), and avoids the use of the cluster approximation. Thi...

Density functional theory (DFT) calculations of the magnetic shielding for solid state nuclear magnetic resonance (NMR) provide an important contribution for the understanding of the experimentally observed chemical shifts. Therefore, methods allowing us to compute those parameters with high precision are very valuable. Recently, we have presented a formalism for computing the NMR parameters in...

DSHIFT is a web server for predicting chemical shifts of DNA sequences in random coil form or double helical B-form. The prediction methods are based on sets of published reference chemical shift values and correction factors which account for shielding or deshielding effects from neighboring nucleotides. Proton, carbon and phosphorus chemical shift predictions are available for random coil DNA...

The Al siting in the ZSM-5 zeolite was investigated by (27)Al 3Q MAS NMR spectroscopy and QM/MM calculations. It was found that the occupation of the framework T-sites by Al and the concentration of Al in these T-sites are neither random nor controlled by a simple rule. They both depend on the conditions of the zeolite synthesis. At least 12 out of the 24 distinguishable framework T-sites of ZS...

The Al siting in the ZSM-5 zeolite was investigated by Al 3Q MAS NMR spectroscopy and QM/MM calculations. It was found that the occupation of the framework T-sites by Al and the concentration of Al in these T-sites are neither random nor controlled by a simple rule. They both depend on the conditions of the zeolite synthesis. At least 12 out of the 24 distinguishable framework T-sites of ZSM-5 ...

The results of first-principles calculations of Al and Sc NMR shielding for a set of ScTT′Al Heusler phase compounds are reported and compared to recently published experimental NMR shifts. The orbital component of the shielding (chemical shift) is computed using density functional perturbation formalism. The spin part (Knight shift) is evaluated using a direct self-consistent approach, where a...

Quantitative structure activity relationship (QSAR) for the anticancer activity of Fe(III)-salen and salen-like complexes was studied. The methods of density function theory (B3LYP/LANL2DZ) were used to optimize the structures. A pool of descriptors was calculated: 1497 theoretical descriptors and quantum-chemical parameters, shielding NMR, and electronic descriptors. The study of structure and...

Theoretical examination of traditional nuclear magnetic resonance (NMR) parameters as well as novel quantities related to magneto-optic phenomena is carried out in this thesis for a collection of organic molecules. Electronic structure methods are employed, and reliable calculations involving large molecules and computationally demanding properties are made feasible through the use of completen...

Significant advances in NMR detection of insensitive, low-frequency spin-l/2 and quadrupolar nuclei have caused rapid progress in the application of transition metal NMR spectroscopy to organometallic chemistry. As a result, the structural dependence of metal NMR parameters, i.e. chemical shifts, heteronuclear and homonuclear spin coupling and relaxation times, has become a topical field of res...