Recently, in situ studies using nuclear magnetic resonance (NMR) have shown the possibility to monitor local transport phenomena of gas-phase reactions inside opaque structures. Their application heterogeneously catalyzed remains challenging due inherent temperature and pressure constraints. In this work, an NMR-compatible reactor was designed, manufactured, tested, which can endure high temper...

The results of a solid-state (11)B NMR study of a series of 10 boronic acids and boronic esters with aromatic substituents are reported. Boron-11 electric field gradient (EFG) and chemical shift (CS) tensors obtained from analyses of spectra acquired in magnetic fields of 9.4 and 21.1 T are demonstrated to be useful for gaining insight into the molecular and electronic structure about the boron...

To investigate the electromagnetic interaction of molecules inside the nanotubes, first, the structure of nanotubes B16N16 was optimized with hybrid density functional theory (B3LYP) using the EPR-II basis set, then Cu, Cu+, Cu++ were located in nanotube and we studied the total energy, band gap energy, electrical potential, changes of band gap energy in terms of total energy and dipole moment ...

α-amylase has been studied extensively from various sides. this enzyme is used in many industries .many applications of this enzyme have encouraged us for greater attempts on the study of α-amylase and to search for more effective processes. in this investigation, the structure of nanotube - catalytic site of bacillus subtilis α- amylase was optimized by hyperchem 7.0 and then it was investigat...

A fundamental chemical question concerning the fullerenes involves their aromatic nature. For many reasons, it is impossible to experimentally obtain anything that is similar to a resonance energy for a fullerene. We must therefore rely on information obtained from magnetic properties. Since fullerenes are borderless polycyclic conjugated systems with internal cavities, it is possible to study ...

We have obtained the 470 MHz 19F NMR spectra of wild type [4-F]Trp-labeled myoglobins (MbCO, MbO2, deoxyMb, metMb, and MbCN) and hemoglobins (HbCO, HbO2, and deoxyHb), as well as those of several mutants (W7F Mb, betaW15F Hb, betaW37S Hb, and betaY130F Hb, all as the carbonmonoxy adducts), prepared via site-directed mutagenesis. The maximum observed chemical shift range induced by folding is 6....

Nuclear magnetic resonance (NMR) is a branch of spectroscopy commonly used for identifying the chemical structure various materials. One areas in which NMR provides accurate data determination nuclear moments. This work reviews experiments with nuclei light elements simple molecules. Since shielding constants from up-to-date quantum calculations are now available, very dipole moments many can b...

the n-(2-benzoyl-phenyl) oxalyl derivatives are important models for studying of three-centered intramolecular hydrogen bonding in organic molecules. the quantum theoretical calculations for two crystal structures of n-(2-benzoyl-phenyl) oxalyl (compounds i and ii) were performed by density functional theory (b3lyp method and 6-311+g* basis set). from the optimized structures, geometric paramet...

The Dopamine has been studied theoretically at the B3LYP/6-31G* level were performed in gasphase. We calculated physical parameters like atomic charges, energy (=>), asymmetry parameter(?), chemical shift @iso, dipole moment and isotropic NMR determinant and in this work we usedGaussian 03 at NMR and calculation by using B3LYP methods with 6-31G* basis set.

The downfield shift of the NMR signal of the bridging proton in a H-bond (HB) is composed of two elements. The formation of the HB causes charge transfer and polarization that lead to a deshielding. A second factor is the mere presence of the proton-accepting group, whose electron density and response to an external magnetic field induce effects at the position of the bridging proton, exclusive...