摘要:

Multiconfiguration valence bond calculations using accurate AO bases have been carried out for F2and F2-. A dissociation energy of at least 1·06 eV is predicted for the F2-ion. Lattice energy calculations together with this value lead to an approximate value of ΔG= -16 kcal mole-1for the reaction

ISSN:0026-8976    

DOI:10.1080/00268977100101341

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Calculations have been made on the predissociation factors for theB3∑u-↔X3∑g-absorption systems of O2and S2to investigate the effect of the centrifugal term in the potential energyBJ(J+ 1)/R2. For most vibrational levels the Franck-Condon factors between the bound state and continuum states are very sensitive toJ. The calculations suggest that accurate line widths are needed for individual rotational levels before reliable repulsive curves can be deduced from this type of analysis.

ISSN:0026-8976    

DOI:10.1080/00268977100101351

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

For certain paramagnetic gases, composed of orbitally non-degenerate molecules, the effects of a magnetic field on the transport properties become independent of the magnitude of the field in the Paschen-Back limit. Instead of being functions ofH/p, they are functions ofζ/p, whereζscales the NS-coupling. This is the explanation of the Senftleben effect in NO2. Similar behaviour is predicted for O2.

ISSN:0026-8976    

DOI:10.1080/00268977100101361

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The molecular reorientational freedom in urea inclusion compounds has been studied for the following long chain molecules: 16-hentriacontanone, 12-bromotricosane, 3-hexadecanone, 1-bromohexadecane. In addition to the classical impedance bridge technique, the depolarization thermocurrent method was used. This technique is characterized by its great sensitivity and allows measurements at low temperatures. Its interest lies in the possibility of separating experimentally the different relaxation processes. The whole body of experimental results cannot be explained by Lauritzen's model. The calculation of the potential energy of interaction between the guest molecules and the host lattice is re-examined here with particular attention directed to the coefficients of the 6–12 Lennard-Jones interaction. As a result of the present work, it appears that the polarization observed by Meakins at high frequency is only partial, whereas the carbon atoms of the urea lattice—whose contribution was neglected by Lauritzen—play a predominant part. Taking into account the modified potential energy of interaction and allowing for a contraction of the lattice, it is possible to propose a reasonable interpretation of relaxation times as slow as those observed (as a general rule five domains are observed).

ISSN:0026-8976    

DOI:10.1080/00268977100101371

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

It is shown that the circular dichroism data from crystalline transition metal complexes ofD3symmetry provides evidence for electric dipole-electric quadrupole contributions to the optical activity, as distinct from the usual electric dipole-magnetic dipole mechanism. Specifically, in

ISSN:0026-8976    

DOI:10.1080/00268977100101381

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Four different phases have been identified in the solid thiourea-cyclohexane inclusion compound in the course of a study of the dependence of the nitrogen pure quadrupole resonance spectrum on temperature. The corresponding transitions can be related to molecular motions. Results of proton magnetic resonance, X-ray diffraction, and micro-differential thermal analysis experiments are presented and an interpretation of the transitions is proposed.

ISSN:0026-8976    

DOI:10.1080/00268977100101391

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Reported herein are the results of iterative spectral analyses based on 100 MHz P.M.R. spectra of threecis,cis-1,4-dialkyl-1,3-butadienes. The couplings thus obtained are discussed in terms of finite perturbation theory calculations on various rotamers and distorted configurations of the butadiene framework. The results are discussed in terms of the proposals of Albriktsenet al.[5]. Partitioning into σ and π contributions is also considered.

ISSN:0026-8976    

DOI:10.1080/00268977100101401

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A classical statistical probability amplitude is introduced whose square modulus is the distribution function. This enables the analogy between classical statistical mechanics and quantum mechanics to be completed. The analogy is developed until quantum statistical derivations can be used in classical statistical mechanics. Two master equations are found: the classical equivalent of the Pauli Master Equation, and a generally valid master equation. Well-known classical equations are deduced from these in a special representation. Interference terms are found and discussed.

ISSN:0026-8976    

DOI:10.1080/00268977100101411

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

It is shown that the perturbation calculation has to be carried to the sixth order to obtain a satisfactory theoretical description of the large Λ-doubling in theA2Π levels of SrH, BaH and BaD. In these cases a fit of Mulliken and Christy's formula to the2Π1/2levels leads to results which seriously disagree with the observed Λ-doubling of the2Π3/2levels. This inconsistency is reduced by working through (extended) second and fourth order formulae, until rather excellent agreement is obtained by the introduction of sixth order terms. Finally the sixth order values of the parameterspandqare inserted in Van Vleck's secular determinant, and a numerical solution of the cubic equation yields results in good agreement with both the observed splitting and the sixth order values.

ISSN:0026-8976    

DOI:10.1080/00268977100101421

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Earlier calculations are extended to the second order in density thus providing the non-additive contributions to the fourth virial coefficient in the presence of a weak three-body force given by the triple-dipole dispersion potential of Axilrod and Teller. We compare the Percus-Yevick approximations of Rushbrooke and Silbert and of Rowlinson at the level of the fourth virial coefficient and find that the former is more accurate. We also compare our calculations of the effective pair potential of liquid argon with the results of Mikolaj and Pings obtained from X-ray diffraction measurements.

ISSN:0026-8976    

DOI:10.1080/00268977100101431

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor