摘要:

Calculations have been carried out to investigate the differences between multiphoton absorption in SF6from the ground vibrational state and low-lying bending-mode states, using currently available estimates of the intermode mixing parametersG3n,S3nandT3n. It is shown that in addition to being anharmonically shifted, the multiphoton absorption spectrum from thev4state is anharmonically broadened and shows less pronounced structure than the equivalent absorption spectrum from the ground state.

ISSN:0026-8976    

DOI:10.1080/00268978400101741

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

In continuation of our previous work the mutual diffusion coefficientD12has been determined for various binary mixtures of the Lennard-Jones (LJ) type by molecular dynamics calculations. The Lorentz-Berthelot combining rules have been applied to all the systems studied.

ISSN:0026-8976    

DOI:10.1080/00268978400101751

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

We extend a previous result, valid for two-dimensional hydrogen atoms, to the three dimensional case. A mapping of a four dimensional spaceR4ontoR3, which establishes an equivalence between Coulomb and harmonic potentials, is used to show that the exact solution of the Zeeman effect problem for highly excited atoms cannot be reached.

ISSN:0026-8976    

DOI:10.1080/00268978400101761

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The osmotic pressure, electric potential and final concentrations in the Donnan equilibrium of a 1-1 electrolyte and a charged species which cannot cross the membrane are calculated in the mean spherical approximation for the primitive model both for equal and different diameters. Large differences with the ideal and Debye-Hückel approximations are found and discussed.

ISSN:0026-8976    

DOI:10.1080/00268978400101771

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The work begun in an earlier paper [Høye, J. S., Stell, G., and Waisman, E., 1976,Molec. Phys.,32,209] is continued. The nature of the singularity that defines the critical point of the fluid described by the Ornstein-Zernike equation with a direct correlation functionc(r) of two-Yukawa form is used to simplify the algebra relating the parameters appearing in its solution. In addition, solutions under the core conditionsh(r) = -1 andh(r) = 0 forr< 1, whereh(r) is the pair correlation function, are related to one another through the study of the more general core conditionh(r) = -ε forr< 1. This relation elucidates a remarkable functional linearity in the solution of the equation as well as defining a generalization of the ‘permeable-sphere model’ used in previous work by one of the authors. The above results represent an important ingredient in the analytic simplification of a two-Yukawa generalized mean spherical approximation and is used in that context in a companion paper. They also permit simplified treatment of the conditions of continuity onh(r) anddh/dratr= 1, which appear in the generalized permeable-sphere model and various other applications. Finally they facilitate the evaluation of critical exponents for the mean spherical approximation with ac(r) of two-Yukawa form forr> 1. In particular, we find δ = 5 and γ = 2 via the compressibility equation, as expected.

ISSN:0026-8976    

DOI:10.1080/00268978400101781

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

We use the results of previous papers in this series to formulate a new self-consistent Ornstein-Zernike approximation for the radial distribution function of a system of particles interacting via a pair potential with a hard core and tail of Yukawa form. The approximation scheme is entirely self-contained, requiring no thermodynamic or other supplementary input. Preliminary results for a simplified version of the scheme that is applicable to a lattice gas yield critical-region thermodynamics in strikingly good agreement with the best current estimates of three dimensional lattice-gas critical behaviour.

ISSN:0026-8976    

DOI:10.1080/00268978400101791

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

ISSN:0026-8976    

DOI:10.1080/00268978400101801

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A simple modification of a high resolution N.M.R. spectrometer is presented, permitting determination of self-diffusion coefficients at pressures up to 200 MPa in the temperature range between 140 K and 450 K. The self-diffusion coefficients of CHF3are determined between 142 K and 250 K. The activation energies derived from the data are [EaD]p= const= (6·1 ± 0·4) kJ mol-1, [EaD]V= const= (3·5 ± 0·4) kJ mol-1. Except for the lowest temperatures, compressed CHF3appears to behave as a normal, rough hard-sphere fluid.

ISSN:0026-8976    

DOI:10.1080/00268978400101811

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

A new way of fittingab initiovalues of the electronic energy of reactive systems is discussed. Following this scheme, the potential energy surface of the Li + HF reaction is built up by matching the functional forms fitted to the different regions of the interaction.

ISSN:0026-8976    

DOI:10.1080/00268978400101821

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The mechanism for vibronic excitation and ion pair production in alkali metal-alkyl halide collisions is investigated. A classical trajectory surface hopping model is developed to account for the fourteen exit channels for which data is available. It is shown that the ground ionic intermediate accounts for the observedAstate excitation in CH3I as well as the production of excited alkali atoms. It is further shown that the other, more highly excited, processes can be understood on the basis of an electron harpoon to form one of a sequence of strongly ionic doorway states. Each doorway state connecting to a manifold of exit channels. The nature of these doorway states and the role of vacancy production in their excitation is discussed.

ISSN:0026-8976    

DOI:10.1080/00268978400101831

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor