A combination of molecular modeling, DFT calculations, and advanced solid-state NMR experiments is used to elucidate the supramolecular structure of a series of benzoxazine oligomers. Intramolecular hydrogen bonds are characterized and identified as the driving forces for ring-shape and helical conformations of trimeric and tetrameric units. In fast MAS (1)H NMR spectra, the resonances of the p...

Abstract Simple reaction procedure, boiling of an equimolar mixture [Re(Cl)(CO) 3 (dppv)] (dppv— cis -1,2-bis(diphenylphosphino)-ethene), 2-(2-pyridyl)benzimidazole (pbi), and TlClO 4 in o -dichlorobenzene solution, leads to two, chromatographically separable, isomers [Re(CO) 2 (dppv)(pbi)] complex. The obtained species, the yellow-emissive [ OC -6–54] orange-emissive -6–53] isomers, have been ...

Magnesium oxide nanotubes of finite length are investigated by the Density Functional Theory (DFT) at the B3LYP/6-31G (d) level. The (6, 0) zigzag and (4, 4) armchair of MgO nanotubes were considered and nuclear magnetic resonance properties including isotropic and anisotropic chemical shielding parameters (CSI and CSA) were calculated for 25Mg and 17O atoms of the optimiz...

A systematic approach has been adopted for structural analysis of Ranitidine Hydrochloride by using FTIR, FT Raman and UV-Vis and NMR spectroscopic techniques. The vibrational analysis are aided by electronic structure calculations HF method and density functional methods (B3LYP) performed with 6-31G(d,p) basis set, with the observed FTIR and FT Raman data, complete vibrational band assignments...

A series of new triazolopyridine-based phosphines has been prepared. These compounds revealed unexpected spectroscopic patterns. In particular, the NMR spectra are highly dependent on the relative conformational preference of the phosphine substituent at C7. Here, we report on their complete NMR analysis, X-ray structures and DFT calculations that confirm the particular arrangement of the phosp...

We report a new classification of silanols in zeolites based on their specific spectral behavior and participation hydrogen bonds combining experimental IR NMR spectroscopic analyses DFT modeling.

In this study the chemical properties of B6C4Si and C16 Clusters connected vitamin C have been investigated using density functional theory (DFT). NMR parameters and HOMO- LUMO Gap energy are calculated by using density functional method (B3LYP) with 6-311G* basis set. Calculations show that HOMO- LUMO Gap energy of vitamin C decreases after connecting to B6C4Si or C16 cluster decreasing of HOM...

The four aldopentoses ribose, arabinose, xylose, and lyxose were evaluated to test their suitability as linear linkers for the formation of intrinsically chiral covalent organic boronic ester networks. Based on X-ray crystal structures of the reaction products with phenylboronic acid, arabinose and xylose formed boronic acid diesters. Lyxose and ribose formed monoesters under the conditions emp...

Abstract The article compares the experimental Fourier transform-infrared, Ultraviolet-visible (UV-vis), and proton nuclear magnetic resonance ( 1 H NMR) spectra of voriconazole fluconazole with density functional theory (DFT) calculations using five different functionals. results were compared previously reported data related to its analogue – posaconazole. analysis calculated infrared (IR) us...

Pentacoordinated iridium(i) complexes of formula IrCl(SiNP)(tfbb) (1) and IrCl(HNP)2(tfbb) (2) (SiNP = SiMe2{N(4-C6H4CH3)PPh2}2; HNP = NH(4-C6H4CH3)PPh2) have been prepared and fully characterised. Both feature a distorted square pyramidal coordination polyhedron at the metal centre in the solid state and are fluxional in solution. Their reaction with trimethyl phosphite yields the derivatives ...