摘要:

The electron resonance spectrum of Coppinger's radical has been measured throughout the nematic range ofp-azoxyanisole and above the nematic-isotropic transition point. Because the proton hyperfine tensors are not cylindrically symmetric about an axis perpendicular to the molecular plane it is possible to deduce not only the mole fraction of radical in the cluster but also its probable orientation within the cluster. Although the results have been interpreted within the framework of the swarm theory we could equally well have used the distortion hypothesis.

ISSN:0026-8976    

DOI:10.1080/00268976600101041

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

A modified Mataga SCF approach is applied to aniline, phenol and toluene. The results obtained are compared with those obtained earlier for the polyacenes and the halobenzenes.

ISSN:0026-8976    

DOI:10.1080/00268976600101051

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The modification of the LCAO (molecular orbital theory) known as ‘ωtechnique’, has been applied to determine the molecular orbitals involved in primary ionization processes of aromatic carbonyl compounds under electron impact.

ISSN:0026-8976    

DOI:10.1080/00268976600101061

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

The thermal conductivity of the systems He-Kr, He-Ar, Ar-Kr and Kr-Ar-He have been measured as a function of composition in the temperature range 30–100°cemploying the thick-wire variant of the hot-wire method. These measured values are compared with the predictions of the Chapman-Enskog theory and the modified Buckingham exp-six potential. Approximate, empirical and different semi-empirical procedures are also tested with reasonable success on the basis of these data.

ISSN:0026-8976    

DOI:10.1080/00268976600101071

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Methods are presented for calculating the expectation value of the spin density for the state resulting from spin-projection of an anti-symmetrized spin-orbital product. It is found that the spin densities for projected and unprojected states differ in the coefficients of the various spatial terms, and that these coefficients can be determined from the properties of the spin algebra. It is shown how the coefficients needed for the spin density are related to those previously derived by other workers for spin-free operators. Illustrative cases of the formalism are examined in detail to show how the calculatedzcomponent of the spin density depends upon the total spin as well as upon itszcomponent.

ISSN:0026-8976    

DOI:10.1080/00268976600101081

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Pyridine and pyridine-d5have been irradiated with gamma rays at 77°Kand the E.S.R. spectra have been studied as a function of temperature up to the melting point of the compounds.

ISSN:0026-8976    

DOI:10.1080/00268976600101091

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

An examination is made of the use of the symmetry group for non-rigid molecules introduced by Longuet-Higgins. A detailed consideration of the energy eigenvectors based on an analysis of intramolecular tunnelling justifies the use of this symmetry group for the purpose of determining the statistical weights and the selection rules for radiative transitions.

ISSN:0026-8976    

DOI:10.1080/00268976600101101

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

摘要:

Fluorine-electron double resonance experiments have been carried out at 3300 and 12 500 gauss on C6F6and CF3CCl3solutions of the free radical tri-tert-butylphenoxyl in order to determine the dependence of the Overhauser effect upon the diffusional correlation time, τc, of the species in solution. τcwas varied by changing the temperature of the sample or by the addition of a chemically inert, miscible solvent which had a much higher (or lower) viscosity than the compounds under study. A scalar contribution to the interaction between the electron of the radical and the fluorine nuclei is evident in these systems and the experimental results have been used to test two current theories of the time-dependence of the interaction. Good qualitative agreement was generally found but neither theory provided a completely satisfactory quantitative description.

ISSN:0026-8976    

DOI:10.1080/00268976600101111

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

ISSN:0026-8976    

DOI:10.1080/00268976600101121

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor

ISSN:0026-8976    

DOI:10.1080/00268976600101131

出版商:Taylor & Francis Group    

年代:1966

数据来源: Taylor