On the magneto-optics of orthoferrites with spin reorientation

The results of magneto-optical investigations into the Γ₂–Γ₄ spin reorientation in an Sm_0.6Tb_0.2Tm_0.2FeO₃ orthoferrite single crystal are reported. The magneto-optical parameters are determined taking into account the dichroism. The orientation of the antiferromagnetic vector in the canted phase is investigated as a function of the magnetic field and temperature. The magnetic anisotropy field strengths are determined by the processing of the results. The orientation contribution to the birefringence is estimated.     

Supersymmetric nonlinear graviton

Branch of Theoretical Problems, USSR Academy of Sciences, Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 26, No. 1, pp. 89–90, January–March, 1992.     

Study of the Electric Strength of Pressed Polyoxide Powdered Materials Obtained by Oxidation of Hard Alloys

The electric strength of a polyoxide mass obtained on the surface of hard alloy composite materials by their high-temperature heating in an electric furnace with direct access of atmospheric air is studied.     

Structural features of glasses in the GaF3-SnF2 system

The structure of 65SnF₂-35GaF₃, 75SnF₂-25GaF₃, and 85SnF₂-15GaF₃ glasses is studied using Raman and IR spectroscopy. The glass structure in the SnF₂-GaF₃ system is formed by a mixed network of fluorogallate and fluorostannate groups. A boson peak is observed in the low-frequency region (～29 cm^?1) of the Raman spectra of the glasses. The shape of the boson peak signifies that the glass does not separate into components on the nanometer scale.     

Structure inhomogeneities of medium-range order in fluorozirconate glasses

Images of cleaved surfaces were obtained for 53ZrF₄-20BaF₂-4LaF₃-3AlF₃-20NaF (ZBLAN) glasses and fused quartz using an NTMDT atomic force microscope. It is shown that the scatter of particle size depends on the cooling rate and is 21–48.5 Å for the cleaved surface of ZBLAN glass obtained by very fast cooling and 68–172 Å for the cleaved surface of ZBLAN after slow cooling. For cleaved fused quartz, the range is 25-18 Å.     

The use of small computers in large-scale activation analysis

This paper describes simple algorithms for evaluating gamma-ray spectra, readily applicable to small computers. A comparative assessment of the accuracy of the existing programs for experimental data analysis is presented. The use of “Nairi-K” computers suitable for “on-line” operation with multichannel analyzers enables as many as 300 element determinations to be carried out in a 7-hour working day.     

Basis Set Orbital Relaxation in Atomic and Molecular Hydrogen Systems

Orbital relaxation (OR) amounts to variation of the orbital exponents in hydrogen molecules and ions relative to the exponents of the isolated atom; it is represented as the sum of the one- and two-center contributions depending on the effective atomic charge and on the presence of other atoms in the molecule. The procedure for isolating the contributions of the exponent includes treatment of the OR of hydrogen in a special set of neutral and charged atoms and molecules with certain multiplicities of their electronic states. Within the framework of the spin-unrestricted Hartree-Fock method, we found and discussed the optimal values of the exponents of the basis orbitals of hydrogen atoms and molecules using the minimal split valence-shell basis set, the basis set that includes the polarization function, and the expanded set of grouped natural orbitals. A simple energy model is suggested for OR. Expressions are derived for evaluating the exponents of the relaxed orbitals in hydrogen-containing systems.Original Russian Text Copyright © 2004 by A. I. Ermakov, A. E. Merkulov, A. A. Svechnikova, and V. V. Belousov__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 973–978, November–December, 2004.