Investigation of longitudinal vibrations of -O-H groups in chrysotile asbestos by neutron scattering and polarized infrared spectroscopy

The specific features of the vibrational spectra of chrysotile asbestos, which is a natural mineral that represents a system of closely packed tubular fibers with an outer diameter of ∼30 nm, an inside diameter of ∼5 nm, and a length up to a centimeter and more, have been investigated using neutron scattering and polarized infrared spectroscopy. This material can serve as a natural matrix for the preparation of nanostructures by filling channels with various materials.     

Gd<Superscript>3+</Superscript> EPR in solid solutions based on ferroelectric lead germanate

The splitting of the ERP spectrum of a single Gd³⁺ ion into four intense components has been observed in crystals of Pb₅(Ge_{1 − x} Si _x )₃O₁₁ solid solutions, which is caused by the appearance of silicon ions in three nearest germanium spheres. The atomic structure of the observed centers has been determined. The conclusion has been made that silicon mainly substitutes for germanium in oxygen tetrahedra and for one of germanuim atoms in oxygen bitetrahedra, which is based on comparison of the measured ratio of component intensities with the results of the calculation of the concentrations of Gd³⁺ associations with silicon ions.     

Fluorosulfation of fluoroalkyl halides

The basic characteristics of fluorosulfation of fluoroalkylhalides (effect of the structure of the polyfluoroalkyl, nature of the halogen, acid catalysis, etc.) with halogen fluorosulfates and peroxydisulfuryl difluoride were investigated. A mechanism was proposed for formation of fluorosulfonic acid fluoroalkyl esters based on the experimental and quantum chemical data.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1718–1732, August, 1992.