Imaging fibrinogen adsorbed on noble metal surfaces with scanning tunneling microscopy: correlation of images with electron spectroscopy for chemical analysis, secondary ion mass spectrometry, and radiolabeling studies

Fibrinogen adsorption on gold and platinum surfaces has been studied with electron spectroscopy for chemical analysis (ESCA), secondary ion mass spectrometry (SIMS), ¹²⁵I labeling, and scanning tunneling microscopy (STM). Stable images of single molecules have been obtained, but are rare. ESCA, SIMS, and labeling studies confirm that absorbed fibrinogen is present on samples at monolayer and submonolayer coverages even when STM images show only a bare substrate. Imaging is more reproducible at high coverages at which single molecules cannot be resolved. Possible explanations for the failure of STM to observe adsorbed fibrinogen molecules are discussed.     

Pressure dependent Raman,and conductivity studies of the fast ion conductors Cu2HgI4, Ag2HgI4 and Tl2ZnI4

High pressure Raman, electrical conductivity, and optical microscopic studies on the ternary fast ion conductor Cu₂HgI₄ were undertaken to delineate the pressure-temperature phase diagram. In addition, comparison of the pressure dependence of Raman shifts in Cu₂HgI₄ and Tl₂ZnI₄ was used to assist in making vibrational assignments whenever possible.     

Effect of loading on intensity of fracture and deformation of polymers

An expression is proposed for the activation energy U = U₀ –a + b², by means of which it is possible qualitatively to describe the various cases of the kinetics of deformation and rupture in polymers.Scientific-Research Institute of Plastics, Moscow. Translated from Mekhanika Polimerov, No. 2, pp. 366–368, March–April, 1972.     

Effect of basis function overlap on intramolecular electron transfer amplitudes: some results for a two-site hubbard model

The effect of overlapping basis functions is detailed for the simplest model (homopolar two-site Hubbard model) of intramolecular electron transfer. Nonvanishing overlap improves, as expected, the quality of the valence-bond wavefunction, but has no strong effect on the exact or molecular orbital transfer amplitude.     

Scaled single-zeta basis set for use with a silicon effective potential: Generalized valence bond description of disilane

A compact and efficient scaled single-zeta basis set has been developed for use in conjunction with the coreless Hartree–Fock silicon effective potential. The scale factors were determined by minimizing the electronic energy of the disilane molecule. Based upon a generalized valence bond computation using this basis, we conclude that the classical concept of localized σ bonds is adequate to fully explain the electronic structure of disilane in analogy to the ethane molecule.