Rhodium(I) pentasubstituted cationic complexes on the basis of 1,2-<Emphasis Type="Italic">O</Emphasis>-Alkylidene-3,5,6-<Emphasis Type="Italic">O</Emphasis>-phosphinetriyl-α-<Emphasis Type="SmallCaps">D</Emphasis>-glucofuranose

Reaction of 1,2-O-alkylidene--D-glucofuranose 3,5,6-phosphites with dicarbonylrhodium(I) acetylacetonate was studied. The structure of the reaction products is determined by the reagent ratio. At a 5:1 molar ratio, the step ligand-exchange process yields chiral complexes of the [RhL₅]⁺acac^– type. Dynamics of and anion exchange in these complexes are considered.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 9, 2004, pp. 1418–1421.Original Russian Text Copyright © 2004 by A. Koroteev, Teleshov, M. Koroteev, and Nifantev.This revised version was published online in April 2005 with a corrected cover date.     

Role of spin in quasiparticle interference

Quasiparticle interference patterns measured by scanning tunneling microscopy can be used to study the local electronic structure of metal surfaces and high-temperature superconductors. Here, we show that even in nonmagnetic systems the spin of the quasiparticles can have a profound effect on the interference patterns. On Bi(110), where the surface state bands are not spin degenerate, the patterns are not related to the dispersion of the electronic states in a simple way. In fact, the features which are expected for the spin-independent situation are absent and the observed interference patterns can be interpreted only by taking spin-conserving scattering events into account.     

Electronic structure of the Zr-He system

Ab initio calculations of the electronic structure of hexagonal close-packed and face-centered cubic zirconium with the impurity of helium atoms of about 6 at % have been performed. It has been established that the presence of helium significantly changes the electronic structure of zirconium and leads to a considerable redistribution of its electron density. Calculated values of chemical shifts of the core states of Zr atoms due to the presence of helium atoms in its lattice have been discussed.     

Synthesis and physicochemical study of diazabicycloundecene hexamolybdochromate [C9H16N2]H3[CrMo6O18(OH)6] · 2H2O

Quinazoline hexamolybdochromate [C₉H₁₆N₂]H₃[CrMo₆O₁₈(OH)₆] · 2H₂O has been synthesized and studied by mass spectroscopy, X-ray powder diffraction, thermogravimetry, and IR and NMR spectroscopy. The compound crystallizes in triclinic system with the unit cell parameters a = 15.06 Å, b = 13.08 Å, c = 8.17 Å, α = 59.85°, β = 123.15°, γ = 107.01°, V = 1165.62 ų, ρ_pycn = 3.58 g/cm³, and Z = 2.     

Hydrogen migration in palladium: First-principles calculations

The supercell Pd₁₆H has been investigated in order to describe the hydrogen migration in the palladium lattice, where the hydrogen atom moves between symmetric interstitial sites. Ab initio calculations of the barriers for hydrogen diffusion in relaxed and unrelaxed metal lattices have been performed in the local density approximation, and the charge transfer during motion of hydrogen has been calculated. The conclusion has been drawn that the hydrogen migration in palladium occurs predominantly along the octapore-tetrapore-octapore trajectory.     

Spectral dependence of the excitation of the “forbidden” second optical harmonic in an aqueous suspension of purple membranes by femtosecond laser pulses under electronic resonance conditions

The spectral dependence of the efficiency of generation of the forbidden (in the electric-dipole approximation) second harmonic (FSH) and its energy on the energy of the excitation pulses is investigated experimentally in a highly disperse suspension of purple membranes containing bacteriorhodopsin (BR) under excitation by femtosecond laser pulses into the single-photon absorption band of BR. The experimental data for the case of resonance excitation attest to an interference character of the interaction of optical nonlinearities of different orders in the process leading to the formation of the FSH signal. Pis’ma Zh. éksp. Teor. Fiz. 67, No. 4, 251–255 (25 February 1998)     

Fabrication of three-dimensional periodic microstructures by means of two-photon polymerization

Received: 7 October 1998