Phase separation in mixtures of colloidal platelets and non-adsorbing polymer: a scaled particle treatment

Scaled particle theory is used to calculate the equation of state for and the free volume accessible to a non-adsorbing polymer, represented by spheres, in a system of colloidal platelets, represented by cut spheres. At low densities the predictions agree very well with computer simulations. For infinitely thin discs, the predictions agree with existing simulation data for the isotropic phase. The analytical results are used to predict the isotropic-isotropic phase boundary as a function of platelet aspect ratio and polymer/colloid size ratio.     

Infrared absorptions and band widths of dilute solutions of CF3H in liquid Ar,N2, and Xe

The spectra of fluoroform (CF₃H) in the solvents Ar, N₂, and Xe have been obtained in the fundamental region (400–4000cm^?1) using a low temperature cryostat and a Fourier transform infrared spectrophotometer. Ab initio calculations at the HF/6-31G? level have been performed to obtain the calculated vibrational frequencies of the isolated CF₃H molecule and CF₃H in the presence of the solvents (Ar, N₂, and Xe). Comparison of the frequency shifts of CF₂H in solution with respect to the gas phase frequencies is made for the experimental and theoretical results. Lorentzian functions were used to fit the bands and obtain the wavenumber at the peak absorbance and the vibrational band widths. An analysis of the dynamics of relaxation has been made based on the infrared time correlation functions for three of the fundamental modes (ν₁, ν₃, and ν₄). Bandwidths, band moments, and relaxation times were obtained by appropriate fitting of the experimental correlation functions to theoretical models. In liquid argon, the temperature dependence of the second moment (M ₂) indicates that rotational relaxation explains the bandwidth of the ν₃ mode. For the ν₄ mode, the temperature dependence of M ₂ can be attributed to rotational relaxation if it is corrected with a Coriolis coupling term. The bandwidths of the ν₁ mode do not follow the rotational relaxation model, and probably vibrational relaxation is the dominant mechanism.     

Periodic Solutions of an Integrodifferential Equation Modelling Resonant Sloshing

This paper considers the problem of finding solutions of which have period 2 and mean 0. The equation models periodicgravity waves on the surface of a shallow rectangular tank whichis oscillating longitudinally near the primary resonance frequency.The singular integral memory term is well behaved, and the Lyapunov-Schmidtprocedure produces bifurcation equations to which the analysisof Hale & Rodrigues on the damped Duffing equation is directlyapplicable. The multiplicity of all small solutions of the equationis found as (µ₁µ₂µ₃) varies in a full neighbourhoodof 0 in R³.     

ChemInform Abstract: Spin Density of the Hexacyanochromate(III) Ion Measured by Polarized Neutron Diffraction.

A Cs₂KCr(CN)₆ single crystal has been investigated by polarized neutron diffraction and the magnetic structure factors obtained are analyzed in terms of valence orbital or alternatively multipole populations on all atoms.