IR spectra of hydrogen fluoride solutions in n-propanol

The densities of solutions of HF in n-PrOH were measured at different mole ratios of the components (from 1 : 12 to 3 : 1), and their IR spectra were recorded. The spectra of all the solutions exhibit absorption bands at 3500, 2600, and 1800 cm^–1 and continuous absorption (CA) in the frequency range from 3500 to 1300 cm^–1. The intensities of these bands and CA increase in proportion to the concentration of HF in solution. The difference between the experimental solution density and the calculated additive sum of the densities of the solution components behaves analogously. The formation of heterocomplexes with a stoichiometric ratio greater than 3 : 1 in the HF solutions in propanol was revealed. These heterocomplexes have large identical structural fragments with the strong quasi-symmetric H-bond. The results of calculations of the stretching vibration frequencies and relative stability of different cyclic pentamers suggest that such a fragment is the most stable cyclic heteropentamer, (HF)₂(nPrOH)₃, in which the HF molecules occupy the neighboring positions.     

Structure of intercalated compounds of graphite fluoride C2FX

Conclusion The results obtained in the present work show that the use of the method proposed in [3] to study the structure of intercalated compounds of graphite fluoride has made it possible to resolve in principle the question of the distribution of the C₂F_X layers along the z axis in these compounds and to determine the nature of the arrangement of the inserted molecules between the layers.In intercalated compounds of stage I with an expanded structure of the filled layer, the molecules of the inserted solvent are distributed chiefly in two layers between the C₂F_x layers, whereas in the compounds with the simple structure they are distributed in one layer.In the intercalated compounds of stage II, the thickness of the unfilled layer is 6 Å, and the thickness of the filled layer coincides with the thickness of the layer in the corresponding inercalated compounds of stage I with the simple structure of the filled layer.The fluorine atoms in C₂F_x are arranged symmetrically on each side of the carbon layer.In the intercalated compounds heated to a temperature of 200°C, the graphite fluoride layers form stacks with a distance of 6.0 Å between the layers.On the basis of the results obtained, it has been suggested that the most probable reason for the strong retention of the inserted component in the intercalated compounds of stage II is the paired linking of the edge sections of the C₂F_x layers.Institute of Inorganic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 29, No. 3, pp. 78–83, May–June, 1988.     

The IR spectra of the products of the reaction of gallium atoms with iodine molecules in solid argon

The IR spectra of the reaction of gallium atoms with iodine molecules from the argon matrix are studied. Most of the bands observed have been assigned to stretching vibrations in tri-, di-, and monoiodide. Both the intensity relationship and the semiempirical estimates indicate that the valence angle should be no more than 110° in gallium di-iodide.     

X-ray spectroscopic study of graphite fluoride (C2F) n intercalated with benzene

Samples of intercalated graphite fluoride of the C₂F·zR type (R is C₆H₆) before and after heating to 150 °C in a spectrometer vacuum chamber were studied by X-ray fluorescence spectroscopy. The C-Kα differential spectra of the samples mainly characterizes the electron state of carbon atoms in the benzene molecule inside the C₂F matrix. The differential spectrum is distinct from the spectrum of solid benzene by additional maxima, which indicate the interaction between the benzene molecules and the graphite fluoride matrix. Comparative analysis of the spectrum of the heated sample and those of graphite and graphite fluoride (CF) _n suggests that the layers of the C₂F matrix contain considerable regions of both completely fluorinated and graphite-like regions. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 705–708, April, 2000.     

Theoretical estimates of the IR spectrum of water intercalated into kaolinite

Calculations at AM1, PM3, and HF/6‐31G levels of part of the IR spectrum of the water–kaolinite intercalated system based on a 96‐atom cluster of kaolinite with one water molecule are reported. Only the water molecule conformation is optimized. Frequencies and intensities for just the water vibrations and stretchings of four cluster hydroxyls were calculated through partial Hessian matrices and polar tensors obtained by numerical differentiation of energy gradients and dipole moment. The water molecule was found to attach to the cluster mainly through a double hydrogen bond to the siloxane inner surface, partially entering the siloxane ring hexagonal hole. Though the theoretical results predict that the water OH stretching frequencies decrease from the gas‐phase state to the intercalated state, they are still higher than expected with respect to the observed spectrum. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009     

Theoretical estimates of the IR spectrum of formamide intercalated into kaolinite

Calculations at PM3 and PBE/6‐31G levels of part of the IR spectrum of the formamide‐kaolinite intercalatation compound based on a 110‐atom cluster of kaolinite with one formamide molecule are reported. Frequencies and intensities for the formamide vibrations and stretchings of four cluster hydroxyls were calculated through partial hessian matrices and polar tensors obtained by numerical differentiation of energy gradients and dipole moment. The formamide molecule attaches to the kaolinite inner surfaces in multiple conformations with its CN bond vector parallel to the surfaces. Hydrogen bonds are formed between the formamide hydrogen atoms (both from NH₂ or CH groups) and the siloxane surface and between the formamide oxygen and nitrogen atoms and the aluminol hydroxyls. The general features of the experimental assignment of the spectrum are confirmed, but the observed splitting of formamide bands is attributed to vibrations from differently attached molecules. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Reaction of graphite fluoride with NaOH-KOH eutectic

Graphite fluoride has been generally considered chemically inert against strong alkalis under ambient conditions. In the present study we demonstrate that treatment of graphite fluoride with eutectic NaOH-KOH mixture at 250 °C induces dramatic structural and textural changes in the solid as evidenced by XRD, FT-IR, Raman, UV-vis absorption and fluorescence and microscopy techniques (TEM, AFM). The reaction proceeds in the molten state leading to water-soluble, graphitized carbon particles which unlike graphite fluoride, adopt a variety of morphologies, like platy, tetragonal, triangular, discoid and spherical. The resulting carbon particles are dispersible in water and fluoresce under UV excitation.     

New products and reaction pathways for the reaction of dimethylsulfoxide with peroxonitrite in aqueous solutions

The first observed basic products of the reaction of dimethylsulfoxide with peroxonitrite were methyl nitrite and methane with pH=7 and methyl nitrate at pH>10. The dependence of the yield of these and other reaction products on pH, concentrations of the substrate and peroxonitrite, and the additives NO ₂ ⁻ and CO₂ was studied. It is proposed that CH₄ and CH₃ONO are formed in the reaction between DMSO and the cis-form of⁻OONO, while DMSO₂ and CH₃ONO₂ are formed in reactions with the trans-form of⁻OONO or the dimer HOONO/OONO respectively. Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 36, No. 1, pp. 41–46, Jaunuary–February, 2000.     

Matrix IR spectra and quantum-chemical calculations of the products of small nickel cluster interactions with water molecules

Reactions of Ni _n clusters with water molecules were studied by IR spectroscopy in inert matrices and quantum chemistry methods. The geometric configurations, total energies, and vibrational frequencies of all the possible Ni₂(H₂O) and Ni₃(H₂O) isomers were calculated. For both systems, the main minima and transition states were found. Water was shown to dissociate to hydrogen and hydroxyl in the reactions, and, in all the complexes formed, hydrogen is situated in the bridge position on the Ni-Ni bond.     

Manganese(II) extraction from chloride nickel solutions with the use of trioctylamine

The influence of the nature of a modificator added to an extraction mixture containing trioctylamine, of the chloride supporting solution concentration, and of temperatures on the manganese(II) extraction from chloride nickel solutions was studied. The composition of an extracted complex was determined. The possibility of using trioctylamine with a 2-octanone addition for deep cleaning of manganese(II) from chloride nickel solutions was shown.     

Molecular structure of a series of epoxysulfolanes and products of their reaction with sodium azide

A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Science Center, Russian Academy of Sciences. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 1, pp. 145–150, January–February, 1992.     

IR spectroscopic studies of natural silk and products of its reaction with sizing components

The reaction mechanism of natural silk with sizing containing the hydrolyzed product of PAN was studied by IR spectroscopy. It was shown that the process took several directions with formation of esters and polypeptide bonds and chemical reaction between the sizing components.