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41.
42.
A series of nitrogen‐tethered allenynes (‘5‐aza‐1,2‐dien‐7‐ynes’) 1 were transformed to the corresponding 3‐acyl‐4‐alkenylpyrrolidines 3 when treated with a catalytic amount of PtCl2 in MeOH at 70°. Initial Pt‐promoted cyclization forms a nonclassical carbocationic intermediate. In contrast to the cycloisomerization in toluene, which produced the bicyclic cyclobutenes 2 , the intermediate is intercepted by addition of an oxygen nucleophile to achieve the formal hydrative cyclization. 相似文献
43.
Shunji Katsumata Katsumi Kimura 《Journal of Electron Spectroscopy and Related Phenomena》1975,6(4):309-319
He(I) photoelectron spectra are reported for various series of chlorine-substituted compounds: (a) CH3CH3?mClm, (b) CH3?mClmCCl3, (c) CH3?mClmCHO and (d) CH3?mClmCOCl, where m = 1, 2 and 3. In each series it is shown that the total sum of vertical ionization energies over all p-type localized molecular orbitals (LO's) has an excellent linear relationship to the number of substituted chlorine atoms. The differences in the total orbital energy sum by successive chlorine substitutions are found to be 26.7 eV for series a and b and 27.2 eV for series c and d, yielding the corresponding experimental σCCl, energies useful for sum rule considerations. The photoelectron spectra of the chloro compounds studied are interpreted with the help of the sum rule as well as CNDO/2 calculations. Orbital correlation diagrams have been constructed for these compounds. 相似文献
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45.
Electron spin resonance experiments at millimeter and submillimeter wavelengths have been performed on the randomly mixed antiferromagnet with competing spin anisotropies, Fe(1?x)CoxBr2. Two antiferromagnetic resonance (AFMR) modes and extra resonances have been observed in the Co-rich concentration region. From the analysis of the AFMR, the anisotropy in the mixtures is shown to become small with concentration. This is a clear evidence for the competition of the anisotropies in these alloys. The extra modes are qualitatively explained as arising from a localized excitation of an Fe2+ spin. 相似文献
46.
An electron spin resonance experiment has been performed on the Cr-rich concentrations of the random mixture Rb2Mn(1-x)CrxCl4 of an insulating ferromagnet (Rb2CrCl4) and an insulating antiferromagnet (Rb2MnCl4). The resonance fields in x = 0.6, 0.7 and 0.8 samples begin to shift towards low field side at temperatures well above the Curie temperatures, when the external field is applied in the c-plane of the crystal. The shift of the resonance field with temperature of the x = 0.7 sample agreed well with that of the x = 0.8 sample, after scaling the temperature axis, while the shift in the x = 0.6 crystal did not. From this observation, we argue that the x = 0.7 and x = 0.8 samples have a long-range ordered ferromagnetic phase below Tc, and that the low temperature phase of the x = 0.6 sample is not a truely long-range ordered one. A weak resonance line was observed in the x = 0.8 sample below about 20 K. This resonance is discussed in connection with the re-entrant spin-glass behavior of this mixed system found in the ac susceptibility measurement. 相似文献
47.
Sho Suzuki 《Colloid and polymer science》1959,167(1):23-25
Zusammenfassung Mittels Elektronenbeugung wurden Versuche durchgeführt, die Hydratationsf?higkeit einiger Metallhalide festzustellen.
Bei den Cd-Haliden nimmt die Hydratationsf?higkeit nach folgender Reihe ab: CdCl2>CdBr2>CdJ2 und bei Metallchloriden nach folgender Reihe ZnCl2>CdCl2>PbCl2>HgCl2>Hg2Cl2 ab.
Diese Ergebnisse entsprechen dem Anionen- oder Kationendurchmesser. Für 80% rel. Feuchtigkeit zeigen Hg2Cl2 und PbCl2 Platzwechsel der Atome. 相似文献
48.
S. Katsumata Y. Achiba K. Kimura 《Journal of Electron Spectroscopy and Related Phenomena》1979,17(4):229-236
The asymmetry parameter (β) of angular distribution of photoelectrons has been obtained with He(I) (58.4 nm) and He(II) (30.4 nm) resonance radiation for several simple compounds (N2, O2, H2O, CO2 and CS2), in order to examine how the β value depends on the excitation energy. It has been found that on going from He(I) to He(II) radiation the energy dependence of β for the nonbonding orbitals of triatomic molecules is similar to that obtained theoretically by Manson for the corresponding atomic p shells. For N2 it has also been found that there is essentially no difference in β values between two vibrational peaks (υ′= 0 and 1) of the first ionisation band in the He(II) spectrum, whereas in the He(I) spectrum an anomalous variation is observed in the β values between the two peaks as originally indicated by Carlson. These results support the interpretation of the autoionisation mechanism suggested by Mintz and Kuppermann. 相似文献
49.
50.