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31.
Eric L. McDowell 《Proceedings of the American Mathematical Society》1998,126(12):3733-3741
The notion of a multi-valued absolute fixed point set (MAFS) will be defined and characterized in the setting of set-valued maps with images containing multiple components.
32.
R. Nakagaki D.C. Frost C.A. McDowell 《Journal of Electron Spectroscopy and Related Phenomena》1981,22(3):289-296
N 1s core-electron spectra have been studied for nitroanilines and related compounds. The spectral data are qualitatively interpreted by means of the molecules-in-molecule method, which describes the interaction between the aromatic amine part (donor moiety) and the nitro group (acceptor moiety) in terms of a composite system consisting of a donor and an acceptor. It was found that the nitro-N 1s spectra and the separation between the nitro-N 1s and the amino-N 1s ionization energies depend upon the magnitude of the intramolecular charge-transfer interaction in the ground state. A similarity between the relaxation effect in the nitro-N 1s or nitro-O 1s core-hole ion and a nitration reaction of the donor moiety is demonstrated. 相似文献
33.
Adelbert Owyoung Peter Esherick Alan G. Robiette Robin S. McDowell 《Journal of Molecular Spectroscopy》1981,86(1):209-215
A near-Doppler-limited isotropic Raman spectrum of the symmetric stretching fundamental ν1 of 28SiH4 has been recorded between 2182.8 and 2187.0 cm?1 using high-sensitivity “quasi-cw” inverse Raman spectroscopy. The band exhibits compact, nonoverlapping J manifolds, which were measured from Q(0) through Q(13), plus a portion of Q(14). Since ν1 is in resonance with the nearby infrared-active stretch ν3, these two bands were analyzed simultaneously using the infrared frequencies of ν3 reported by Cabana, Gray, Robiette, and Pierre. The results confirm their analysis, in which several perturbation-allowed ν1 transitions were identified in the infrared, but the molecular constants for the v1 = 1 state are much better determined with the inclusion of the Raman data. At higher J, ν1 exhibits significant intensity perturbations due to a breakdown of the selection rule ΔN = 0; these have been quantitatively accounted for. 相似文献
34.
J.C. Bunzli D.C. Frost F.G. Herring C.A. McDowell 《Journal of Electron Spectroscopy and Related Phenomena》1976,9(3):289-305
The He(I) photoelectron spectra of Cl2CCH2, Cl2CCF2, Cl2CF2 and Cl2CBr2 have been recorded. Detailed assignments of the 相似文献
35.
36.
Lyman R. Caswell James E. Hardcastle Thomas A. Jordan Iftikhar Alam Karen A. McDowell Cynthia A. Mahan Frank R. Fronczek Richard D. Candour 《Journal of inclusion phenomena and macrocyclic chemistry》1992,13(1):37-45
18-Crown-6 and dicyclohexano-18-crown-6 complexes of potassium 2- and 4-nitrophenoxide, and 18-crown-6 complexes of thallium(I) 2- and 4-nitrophenoxide have been synthesized. Solvent effects on the visible spectra of the nitrophenoxide anions are independent of the nature of the cation and the nature of the complexing agent. The 18-crown-6 complex of thallium(I) 2-nitrophenoxide is a 1:2 complex. All the other complexes are 1:1. X-ray crystallographic examination of the potassium dicyclohexano-18-crown-6 complexes showed the potassium ion is octacoordinated in the 2-nitrophenoxide and heptacoordinated in the 4-nitrophenoxide. 相似文献
37.
R.F. Holland M.C. Vasquez W.H. Beattie R.S. McDowell 《Journal of Quantitative Spectroscopy & Radiative Transfer》1983,29(5):435-438
From observations of the spectral absorbance of mixtures of nitric oxide in nitrogen at room temperature, we derive an integrated absorptivity for the NO fundamental band of 137.3±4.6 cm-2 atm-1 at 0°C. The indicated uncertainty is the estimated maximum error. 相似文献
38.
H.Keith McDowell 《Chemical physics》1982,72(3):451-455
The neutralization of ions impinging on a substrate is modeled by treating the substrate as both a two-dimensional, tight-binding, semi-infinite sheet and a two-dimensional, tight-binding, infinite sheet. In both cases the equations of motion are set up in a generalized Langevin format. Results are presented for a model interaction and compared with previous computations using a semi-infinite chain model and an infinite chain model. 相似文献
39.
Chris W. Patterson Herbert Flicker Robin S. McDowell Norris G. Nereson 《Molecular physics》2013,111(3):517-526
A high resolution diode laser absorption spectrum of the ν9 R Q 0 branch of C2H6 at 822 cm-1 reveals a rotational progression with anomalous spacing and intensity, which is shown to be a result of both l-doubling and torsional splitting of rotational levels, both of which give rise to a J(J+1) energy dependence. From a contour analysis of the spectrum we estimate values for the l-doubling and torsional splitting parameters. 相似文献
40.
A systematic method of obtaining relative signs of hyperfine coupling constants is described. It applies to systems consisting of (a) a set of one or more nuclei coupled fairly strongly to the electron spin, and possessing a two-fold (or higher) axis of symmetry, together with (b) a set of weakly coupled nuclei defining superhyperfine transitions. ENDOR measurements for several E.P.R. hyperfine transitions, with the field oriented along the symmetry axis, give relative signs of hyperfine components for this direction. Signs for the other directions can then be obtained through ENDOR measurements on a single hyperfine transition at various field orientations. Additional double ENDOR measurements may be necessary for very weakly coupled nuclei. This method can complement double ENDOR studies in favourable cases. It is illustrated by the determination of signs of coupling constants of protons and of 75As in the AsO4 4- radical in KH2AsO4. 相似文献