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The solid-state NMR spectroscopy technique is employed to study and describe the coupling of functional hydrogen bonds in the models of the confactor pyridoxal-5'-phosphate (PLP) with carboxylic acids that mimic the confactor of various enzyme active sites. The analysis proves a shift in the proton to the Schiff based nitrogen, followed by an increase in the positive charge of the nitrogen atom, which can be avoided by introducing an aromatic substituent in the model.

The phosphate ions HPO4(super 2-) and H2PO4(super -1) are analyzed since sizable solvation effects are expected for the IR spectra of these strongly polarizable ions. The widths, intensities, and spectral positions of the resultant bands are compared with experimental IR spectra for the purpose of checking the computational procedures, which provide insights into the merits and limitations of the available density functional theory (DFT)/molecular mechanisms (MM) approach to the prediction of IR spectra in the condensed phase.

The series of amorphous nitrided galloaluminophosphate 'AlGaPON' catalysts with nitrogen contents varying from 0 to 23.3 wt% were obtained by nitriding Al(sub 0.5)Ga(sub 0.5)PO(sub 4) precursor under ammonia flow at 750 degreeC in a tubular furnace. The results compared by using X-ray absorption spectroscopy (XAS) and X-ray photoelectrons spectroscopy on five samples is described.

Isotope-edited Fourier transform infrared (FTIR) spectrometry complemented by homology modeling and quantum chemical calculations are used for analyzing the orotate hydrogen-bond network for Plasmodium falciparum orotate phosphoribosyltransferase (PfOPRT). The results have provided reaction coordinate information for the PfOPRT-catalyzed orotidine 5E-monophosphate (OMP) and transition-state analysis has supported a dianionic orotic acid (OA) leaving group.

A combined nuclear magnetic resonance (NMR) experimental and periodic density functional theory (DFT) computational study of the environments and periodic density functional theory (DFT) computational study of the environments and electronic structures occurring in a range of paramagnetic Fe(III) phosphates is described. The [super 31]P spin-echo mapping and [super 7]Li magic angle spinning NMR methods have produced the hyperfine shifts of the species of interest, which is complemented by periodic hybrid functional DFT calculations of the respective hyperfine and quadrupolar tensors.

A new type of fluorophosphate glasses with high thulium doping concentration is examined and the intensive 1.8 [micro]m fluorescence is shown with lower concentration quenching. Raman spectroscopy has shown that the glass structure will be changed when adding [Tm.sup.3+] ions into fluorophosphate glasses.

The REfocused INADEQUATE spin-Echo (REINE) NMR spectroscopy method is employed to study the J coupling and chemical shift two-dimensional correlations in disordered solids. The quantification of the various J couplings is also presented.

The article presents comparative studies of the temperature-dependent spectroscopic properties of germanate, silica, and phosphate glasses that are doped by thulium, [Tm.sup.3+]. These glasses are shown to be widely used in the fiber dlasers that are used in the eye-safe wavelength region.

A combination of the ab initio calculations and electron transmission spectroscopy is employed to determine the presence of [pi.sup.*] shape resonances in the temporary anion states of trimethyl phosphate and other compounds bearing the phosphate group.

The syntheses of 2-C-methylerythritol 4-phosphate (MEP), 2,4-cyclodiphosphate and various other MEP analogues by using the dioxanone approach is discussed.

The decarboxylation of orotidine 5'-monophosphate (OMP) catalyzed by orotidine 5'-monophosphate decarboxylase in a solvent of [H.sub.2]O/[D.sub.2]O is reported. Equal amount of [6-[super 1]H]-uridine 5'-monophosphate and [6-[super 2]H]-uridine 5'-monophosphate decarboxylation are yielded.

The syntheses, Raman spectra, and crystal structures of four new metal(II) hexafluorophosphates(V) containing Xe[F.sub.2] as ligands are described. It presents that Raman spectrum of the bulky belongs to the same compound that was structurally characterized.

A research is conducted to evaluate the effect of the cavitand's environment on polar interactions shielded from the aqueous solution outside. Findings reveal that folds around a cationic guest, temporarily locks it in a defined environment, and stabilizes a buried polar interaction similar to the favorable cases measured in proteins.

A spectroscopic analysis is performed on trivalent erbium ions Er(super 3+), doped into calcium fluorophosphate (FAP) to assess the material for its potential as a near-infrared laser host. The Judd-Ofelt model is applied to the orientation-averaged, room-temperature absorption intensities of Er(super 3+) in FAP to obtain the phenomenological intensity parameters.

A spectroscopic Judd-Ofelt investigation was performed on Er(super 3+) in the doubly doped phosphate glass: Er(super 3+), Yb(super 3+) to assess the potential of Er(super 3+) as a laser system. It could be concluded that the phosphate glass: Er(super 3+), Yb(super 3+) is an excellent contender for Q-switched eye safe laser at 1.54 (micron)m and can be efficiently pumped at 980 nm using a powerful diode.

A series of niobate-phosphate and niobate-silicate glasses doped with Eu(super 3+) ions were prepared. The emissions, phonon-side band spectra and fluorescence lifetimes of these glasses were studied.