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81.
FB Alhanash NA Barnes AK Brisdon SM Godfrey RG Pritchard 《Dalton transactions (Cambridge, England : 2003)》2012,41(34):10211-10218
The reactions of the group 15 trihalides, MX(3) (M = As, Sb, Bi; X = Cl, Br), with the phosphine selenide SeP(p-FC(6)H(4))(3) result in the formation of co-crystals of formula MX(3)·SeP(p-FC(6)H(4))(3). No reaction was observed with MI(3) (M = As, Sb, Bi). The structures of MX(3)·SeP(p-FC(6)H(4))(3) (M = As, X = Br 2; M = Sb, X = Cl 3; M = Bi, X = Cl 5; M = Bi, X = Br 6) have been established, and are isomorphous, crystallising in the cubic I23 space group. All the structures feature a primary MX(3) unit, which has three weak secondary MSe interactions to SeP(p-FC(6)H(4))(3) molecules. However, each of these SeP(p-FC(6)H(4))(3) molecules bridges three MX(3) molecules, resulting in the generation of an M(4)Se(4) (M = As, Sb, Bi) distorted cuboid linked by the pnictogen-chalcogen interactions. Four opposing corners of the cuboid are occupied by the M atom (M = As, Sb, Bi) of an MX(3) pyramid, and the other four by the selenium atom of the phosphine selenide. 相似文献
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Ronald D. Brown Peter D. Godfrey Alfred L. Ottrey 《Journal of Molecular Spectroscopy》1980,82(1):73-80
The microwave spectrum of 2-cyanoaziridine has been measured and assigned. Only the spectrum of the cis isomer has been detected although extensive searches for transitions from the trans isomer have been made, suggesting that it is at least 11 kJ mol?1 less stable. The following nuclear quadrupole coupling constants were obtained: χaa(1) = ?1.249(14), χbb(1) = 1.407(12), χaa(2) = ?3.547(6), χbb(2) = 1.865(8) MHz, the former pair probably referring to the amino nitrogen and the latter pair to the nitrile nitrogen. The rotational constants derived from the analysis are: A = 16877.718(32), B = 3528.931(4), C = 3373.065(4) MHz, DN = 1.10(4) kHz. 相似文献
86.
Godfrey Brendan B. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1977,5(4):223-230
Computational and analytic studies of the Autoresonant Acceleration proposal for collective ion acceleration are presented. Linear theory is reviewed, the electrostatic well depth is estimated nonlinearly, and an electron beam envelope equation is derived and solved. Two-dimensional numerical simulation results are given. Together, these calcualtions demonstrate unneutralized electron beam equilibrium in a diverging magnetic guide field, the behaviour of large amplitude slow cyclotron waves in the beam, and the acceleration of test ions over short distances in the wave troughs. In addition, the computer simulations point up the need for improved understanding of the linear theory of radially inhomogeneous noneutral beams and for methods of suppressing radial modulation at the diode-waveguide interface. 相似文献
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The observed low values and striking variations in kaonic X-ray intensities were found to be not due to K? decay. Measurements on H2O and CH show greatly reduced X-ray intensities apparently due to the presence of the hydride bonds. A simple cascade calculation with an initial distribution in n = 30 that is statistical out to various lmax gave agreement with our absolute X-ray intensities. A correlation between lmax and atomic spacing is suggested. 相似文献
89.
Ronald D. Brown Peter D. Godfrey Donald McNaughton Anthony P. Pierlot William H. Taylor 《Journal of Molecular Spectroscopy》1990,140(2)
A new Stark-modulated submillimeter-wave spectrometer is described. This spectrometer has been used to analyze the microwave spectrum of three isotopomers (heavy atoms) of ketene. The rotational constants determined have been used to calculate the structure of ketene using a variety of methods. The question of planarity of ketene is also addressed. High-resolution microwave measurements have been used to determine the spin-rotation interaction in CH213CO. 相似文献
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