摘要:

Force constants are calculated for sulphur hexafluoride employing a valence force field and a central force field (Orbital Valency Force Field [5]). Both force fields yield the same root-mean-square vibration amplitudes to two significant figures, and the calculated values agree with an experimental determination.

ISSN:0026-8976    

DOI:10.1080/00268976200100221

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Electron spin resonance spectra of irradiated crystals of ammonium hypophosphite (NH4)+(H2PO2)-indicate that the ionic radical HṖO2-is initially formed. The hyperfine interaction tensor of the phosphorus nucleus has the principal values 1698, 1228 and 1228 Mc/s. Interaction with the proton gives rise to an almost isotropic hyperfine coupling of 230 Mc/s. These results indicate that the species HṖO2-is irregular tetrahedral in shape, the unpaired electron occupying a hybrid σ orbital centred on the phosphorus nucleus.

ISSN:0026-8976    

DOI:10.1080/00268976200100231

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

In certain stable free radicals the unpaired electron, predominantly localized on a carbon atom, interacts magnetically with protons two bonds removed, with consequent hyperfine structure of the electron spin resonance spectrum. The anisotropic component of the coupling tensor which describes the interaction is assumed to have two important contributions :1.(1) the direct dipole-dipole interaction of the free spin localized on the carbon atom;2.(2) the effect of free spin on the intervening atom.

ISSN:0026-8976    

DOI:10.1080/00268976200100241

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The ionic radical SO3-has been identified inγ-irradiated single crystals of sodium dithionate, sulphamic acid, potassium sulphamate, potassium amine disulphonate and potassium methane disulphonate. The electron resonance spectrum is a single line with an isotropicgfactor of 2·004. The principal values of the33S hyperfine coupling tensor are 428, 314 and 316 Mc/s, from which the percentages of 3s and 3p character of the unpaired electron orbital are obtained, enabling a value of 111° for the O-S-O angle to be deduced. Ultra-violet transitions at 2700åand 2400åwere found for SO3-. A value of 104for the extinction coefficient of the 2400åband was measured. A comparison of spin populations between the isoelectronic species PO3=, SO3-and ClO3is included.

ISSN:0026-8976    

DOI:10.1080/00268976200100251

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The electron spin resonance spectra of the radical CH(SO3)2=trapped in a single crystal of potassium methane disulphonate and of the isoelectronic radical N(SO3)2=in the isostructural potassium amine disulphonate crystal are interpreted. The hyperfine couplings for H,13C and14N nuclei and theg-factors are given. The unpaired electron occupies a π-orbital of predominantly central-atom 2p character in each case. The spin populations are derived. An unusual feature, prominent in the potassium methane disulphonate case, is the detection of resolved hyperfine coupling to hydrogen nuclei in the host molecules.

ISSN:0026-8976    

DOI:10.1080/00268976200100261

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Spectra of some Cu and Ni chelates of Schiff's bases are discussed. We conclude that interpretation of the band polarizations of the centric chelates must await a detailed vibronic calculation. Evidence is cited to show that the prominent green band of Cu chelates of Schiff's bases is the (x2-y2) « (xy) transition. Pure electronic selection rules of acentric Cu chelates are discussed and used.

ISSN:0026-8976    

DOI:10.1080/00268976200100271

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The problem of electron binding in solutions is treated on the basis of a continuum model. The polarizable medium is represented by a continuum, which can be characterized by macroscopic properties, e.g. the static and the optical dielectric constants. The motion of an additive electron is determined by its interaction with the polarization produced by the electron itself. An attempt is made to treat the whole system (dielectric medium and additive electron) by employing two different approximations.

ISSN:0026-8976    

DOI:10.1080/00268976200100281

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

Moderately strong, very broad absorption bands observed in dilute lanthanide bromide solutions in nearly anhydrous ethanol are interpreted as electron transfer from the highest filled M.O. to the partly filled 4fshell in the case of Nd(III), Sm(III), Eu(III), Tm(III) and Yb(III). Good agreement is obtained with a theory taking its parameters from the internal 4ftransitions. Electron transfer bands are also observed for Eu(III) and Yb(III) dialkyldithiocarbamates, and the narrow bands of similar Pr(III), Nd(III), Sm(III) and Eu(III) complexes are briefly discussed. Relatively narrow 4f→5dtransitions are observed in the Ce(III), Pr(III) and Tb(III) bromide solutions and related to the same theory. As expected, no bands are observed for Gd(III), Dy(III), Ho(III), Er(III) and Lu(III).

ISSN:0026-8976    

DOI:10.1080/00268976200100291

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The Platt electrostatic model of a diatomic hydride is modified by the introduction of a scale factor which depends on the internuclear distance. This has the theoretical advantage of enabling the molecular virial theorem to be satisfied and the practical advantage, as shown by some examples, of improving the agreement with experiment particularly for the lighter molecules. The calculation of the scale factor requires two more integrals but the equilibrium internuclear distance and the force constant can still be interpreted electrostatically.

ISSN:0026-8976    

DOI:10.1080/00268976200100301

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor

摘要:

The electron spin resonance spectra of the biphenylene cation and anion and the binaphthylene anion are described. The proton hyperfine splitting constants for the ions derived from biphenylene are in good agreement with predictions based on molecular orbital calculations. The results for the binaphthylene anion are less satisfactory.

ISSN:0026-8976    

DOI:10.1080/00268976200100311

出版商:Taylor & Francis Group    

年代:1962

数据来源: Taylor