The transformation of second-rank Cartesian tensors under rotation plays a fundamental role in the theoretical description of nuclear magnetic resonance experiments, providing the framework for describing anisotropic phenomena such as single crystal rotation patterns, tensor powder patterns, sideband intensities under magic-angle sample spinning, and as input for relaxation theory. Here, two eq...

The ruthenium-containing sensitizing dye N719 grafted on TiO2 nanoparticles was investigated by solid-state NMR. The carbon resonances are assigned by means of (13)C cross-polarized dipolar dephasing experiments. DFT calculations of the carbon magnetic shielding tensors accurately describe the changes in chemical shifts observed upon grafting onto a titania surface via one or two carboxylic fun...

Dependence of NMR isotropic shift averages and nuclear shielding tensors on the internal rotation of the functional group X about the C± X bond in seven simple vinylic derivatives H2C5 CH± X M. BAADEN , P. GRANGER and A. STRICH* UMR 7510, Laboratoire de Re sonance Magne tique Nucle aireÐ RM3 UMR 7551, Laboratoire de Chimie Quantique, Universite Louis Pasteur, 4 rue B. Pascal, 67000 Strasbou...

The magnetic shielding tensors of protons of water in barium chlorate monohydrate are investigated at room temperature by means of solid-state NMR spectroscopy, both for static powders and under magic-angle spinning conditions, using oneand two-dimensional techniques. First-principles DFT calculations based on a periodic planewave pseudopotential formalism for a static periodic system provide s...

Ab initio values of Nitrogen N Nuclear Quadrupole Coupling Constants (NQCC's) are calculated for a series of methyl-substituted azoles in the Multiconfigurational SCF (MCSCF) approximation. The four triazoles and two tetrazoles studied here are all isoelectronic. This enabled us to use the same level of approximation basis set and active space for all the molecules. The computed NQCC's are used...

51V NMR Spectra, Oxovanadium, Nitrosylvanadium, Hydroxylamidovanadium The 51V NMR spectra are recorded for 3 dinuclear complexes {VO (ONR2 )2 O and 13 mononuclear vanadium (-f V) and (+III) chelate complexes of the general formula [VXYZ]Q, where X = 02-, NO"; Y = 02~, 022" , R2NO~; and Z = picolinate-(pic), dipicolinate2(dipic), nitrilo-tri(2-propanolate)3_, and o-phenanthroline (phen). Shieldi...

A method is described for measuring absorbed electromagnetic energy radiated from cell phone antennae into ex vivo brain tissue. NMR images the 3D thermal dynamics inside ex vivo bovine brain tissue and equivalent gel under exposure to power and irradiation time-varying radio frequency (RF) fields. The absorbed RF energy in brain tissue converts into Joule heat and affects the nuclear magnetic ...

The exact knowledge of hydrogen atomic positions of O-H···O hydrogen bonds in solution and in the solid state has been a major challenge in structural and physical organic chemistry. The objective of this review article is to summarize recent developments in the refinement of labile hydrogen positions with the use of: (i) density functional theory (DFT) calculations after a structure has been d...

We have derived analytical expressions for determining the orientation of high-symmetry single crystals from line-crossings in a single rotation plot. We demonstrate the utility of the method using the strontium-87 resonance in strontium nitrate. Employing our new method, which we call orientation of single crystals using linear approximations to NMR transits (OSCULANT), in combination with fou...

Direct evaluation of the induced π current density in [5]paracyclophane (1) shows that, despite the significant non-planarity (α = 23.2°) enforced by the pentamethylene bridge, there is only a modest (ca. 17%) reduction in the π ring current, justifying the use of shielding-cone arguments for the assignment of (1)H NMR chemical shifts of 1 and the claim that the non-planar benzene ring in 1 ret...