摘要:

Configuration interaction, vibronic coupling and thermal population of excited states are all expected to occur in the alkyl cyclooctatetraene anions. The importance of these effects in determining the electron resonance spectra of these species is investigated theoretically and the results compared with experiment. It is concluded that vibronic coupling plays an important role.

ISSN:0026-8976    

DOI:10.1080/00268976600101441

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

A single centre wave function for H2O consisting of 19 determinants is obtained. Each determinant is composed of Slater type orbitals having non-integer principal quantum numbers. Up toforbitals are considered and in the final wave function there are 19 linear and 36 non-linear parameters; these are determined variationally. The total molecular energy is found to be -75·8611a.u.(-76·4606), the bond distance to be 1·714a.u.(1·81) and the breathing force constant to be 1·13a.u.(1·07), where the values in parentheses are those determined experimentally.

ISSN:0026-8976    

DOI:10.1080/00268976600101451

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The positive Overhauser enhancement observed for thetert-butyl groups oftri-tert-butyl phenol in solutions oftri-tert-butyl phenoxyl radical has been shown to be associated with the proton exchange between the radical and phenol molecules. It is postulated that in the radical molecule the scalar coupling between the electron and thetert-butyl protons occurs at least in part by a hyperconjugative mechanism and therefore the coupling is modulated by random rotation of thetert-butyl groups. This leads to a positive polarization of thetert-butyl protons, which persists when the radical accepts a proton and becomes atri-tert-butyl phenol molecule.

ISSN:0026-8976    

DOI:10.1080/00268976600101461

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The difficulties of the classical theory of simple fluids can be reduced to one of determining the form of the weak long-range component of the direct correlation function. It is suggested that this component can, as an approximation, be regarded as a measure of the lack of mutual interference of parallel chains of molecular correlations. This view leads to simple functional forms for the component and so to equations of state. The results are compared with those of the first and second versions of the Percus-Yevick and hyper-netted chain approximations and are shown to be of similar accuracy to the latter, but more tractable.

ISSN:0026-8976    

DOI:10.1080/00268976600101471

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The factors affecting the electron resonance linewidths of a biradical, showing strong spin exchange, tumbling isotropically in solution are considered. For a biradioal with two equivalent magnetic nuclei the hyperfine lines should alternate in width provided the dominant relaxation mechanism is a modulation of the exchange interaction between the unpaired electrons. Certain nitroxide biradicals do indeed exhibit an alternating linewidth effect which we attribute to this mechanism.

ISSN:0026-8976    

DOI:10.1080/00268976600101481

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Chemical shifts of the nuclear resonances of23Na,39K,87Rb and133Cs in aqueous solutions of alkali halides and nitrates from concentrations of 0·2 molal up to saturation are recorded. The magnitudes of the shifts increase considerably with increasing atomic number of the cation, and shifts to both higher and lower fields relative to the cation at infinite dilution are observed.

ISSN:0026-8976    

DOI:10.1080/00268976600101491

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The electron spin resonance of an x-ray irradiated single crystal of potassium dihydrogen arsenate has been examined and a radical which is thought to be AsO44-identified. Analysis of the spectra for various orientations of the crystal with respect to the external magnetic field leads to an axially symmetric hyperfine interaction tensor which is in agreement with what would be expected for the AsO44-radical.

ISSN:0026-8976    

DOI:10.1080/00268976600101501

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Theoretical electron resonance line shapes have been calculated for dynamically distorting octahedral copper complexes. Comparison with published experimental data leads to an estimate of the activation energy for such processes.

ISSN:0026-8976    

DOI:10.1080/00268976600101511

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The interaction of adsorbed molecules with molecules of the underlying solid undergoing thermal oscillations is discussed and calculated. The friction coefficient for the adsorbed molecules has been evaluated by means of some approximate formulae and compared with the experimental data. The kinetic equations describing a non-uniform state of adsorbed gas has been solved by the Chapman-Enskog perturbation method. The phenomena of surface diffusion, thermal diffusion, thermal conduction and viscosity are discussed on the basis of the second approximation of this method. The application of this theory to the separation of components of adsorbed gas by surface flow is described in detail. The theory of surface separation of isotopes is also discussed and compared with experimental data.

ISSN:0026-8976    

DOI:10.1080/00268976600101521

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

ISSN:0026-8976    

DOI:10.1080/00268976600101531

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor