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21.
22.
CuAl2Cl8. Preparation and Crystal Structure. Crystals of CuAl2Cl8 have been prepared. Their remission spectrum agrees with that of gaseous CuAl2Cl8. The crystal structure (P21/c;a = 6.614, b = 7.376, c = 12.319 Å; β = 94.11°) shows a molecular lattice with Cu in square planar coordination, which is completed to a stretched octahedron (as in solid CuCl2) by two Cl atoms from neighbour molecules. Al has tetrahedral coordination. 相似文献
23.
The Catalysed Volatilization of Red Phosphorus and of Claudetite The catalysis of the volatilization of Pred (as P4) by AlCl3,g, and of the volatilization of claudetite (as As4O6) by I2,g is observed by mass spectrometry. 相似文献
24.
Keller Hildegard Langer Elisabeth Lehner Harald Derflinger Gerhard 《Theoretical chemistry accounts》1978,49(2):93-100
The Algebraic Theory of Chirality Functions is derived by means of exclusively qualitative considerations. Hence, the significance of quantitative results is questionable. Moreover the construction of “Näherungsansätze” (”Approximation-Ansatz”), which may be interpreted as semiempirical methods, is achieved on the basis of plausibility and mathematical simplicity. Since physical arguments are not included, the consistency or inconsistency of “Näherungsansätze” with experimental results do not justify direct physical conclusions. 相似文献
25.
26.
The 1D- and 2D-6Li, 6Li-INADEQUATE experiments are described as new tools for the detection of scalar coupled nonequivalent 6Li nuclei in organolithium clusters. Practical applications of these sequences are demonstrated for the 6Li-NMR spectra of (E)-1-lithio-2-(2-lithiophenyl)-1-phenylhex-1-ene ( 1 ) and (E)-2-lithio-1-(2-lithiophenyl)-1-phenylpent-1-ene ( 2 ), where signals due to dimers and monomers can be distinguished. The performance of the 2D-6Li, 6Li-INADEQUATE and the 6Li, 6Li-COSY-45-LR experiment are compared. The 6Li chemical shifts of 1 and 2 are discussed. 相似文献
27.
Hiller W Brüll A Argyropoulos D Hoffmann E Pasch H 《Magnetic resonance in chemistry : MRC》2005,43(9):729-735
The application of HPLC-NMR for the analysis of a mixture of fatty alcohol ethoxylates (FAEs) is described. The use of the new generation, cryogenically cooled probes is investigated in respect of the sensitivity advantage that they provide. The FAE mixture is separated using liquid chromatography at the critical point of adsorption. The ability of the method to differentiate between the different end groups and the degree of polymerization of the mixture constituents is investigated. Both on-flow and stop-flow HPLC-NMR techniques were used together with two-dimensional NMR spectroscopy. The results are compared with those obtained by using an evaporative light scattering detector for the HPLC. 相似文献
28.
Conclusion We have considered allNN-partial waves simultaneously. The central part of the one gluon exchange is always repulsive, the tensor part can be neglected and the spin-orbit part is too weak for this choice of parameters. An additional colourless VMEP potential allows us to reproduce the experimental data. However, this potential cannot be related to a long range one-pion exchange potential.Presented at the symposium Mesons and Light Nuclei, Bechyn, Czechoslovakia, May 27–June 1, 1985. 相似文献
29.
Harald Schfer 《无机化学与普通化学杂志》1974,410(3):269-273
The Chemical Transport of Platinum with Chlorine Experiments show that the chemical transport of platinum by means of chlorine within a temperature gradient at temperatures below ≈ 1000°K goes into the hot temperature region, but at higher temperatures in the reverse direction. From the thermodynamic discussion it can be seen, that the platinum content of the gas phase at low temperatures is governed by the exothermic formation of Pt6Cl12,g, and at higher temperatures by the endothermic formation of PtCl3,g and PtCl2,g. The platinum content of the gas phase passes a minimum at ≈ 1000°K, if P(Cl2) = 3.5 atm. This result is in agreement with the observed inversion of the transport direction. 相似文献
30.
Mass Spectroscopic Observations and Chemical Transport Experiments with the Systems VCl3/Al2Cl6 and VCl2/Al2Cl6 By mass spectrometry the equilibrium VCl3,s + 0.5 Al2Cl6,g ? VAlCl6,g has been determined: ΔH°(298) = 25.6(±0.5) kcal; ΔS°(298) = 23.0(±3) cal/K, ΔCp (assumed) = ?4 cal/K. This is approximately in agreement with results determined by ligand field spectroscopy by ANUNDSKÅS and ØYE (A. and Ø.). For the dimerization of VCl3,g values for ΔH and ΔS have been derived. The molecule VAl2Cl9 assumed by A. and Ø. could not been observed by mass spectrometry. For the VCl2/Al2Cl6 complex, observed by chemical transport, A. and Ø. give the formula VAl3Cl11. This molecule could not been observed by mass spectrometry. This suggests a smaller concentration, compared with the results of A. and Ø. Stabilization of VCl2,s (by metal-nietal-bonds) shifts the reaction to the left, whith explains the lower complex concentration as well as the larger molecular weight of the complex. With chlorides stabilized by stronger metal-metal bonds (MoCl3, MoCl2, Nb3Cl8) AlCl3 complexes are not formed in observable concentrations. The chemical transport of VCl2 with Al2Cl6 needs relatively high temperatures (973 → 873 K). In this case the addition of SiCl4 hinders the attack of the quartz ampoule by Al2Cl6. Using a VCl3 + VCl2 mixture, VCl3 is transported by Al2Cl6 (673 → 623 K) into the colder region. If afterwords the ampoule is reversed, VCl3 again moves into the colder region, but the thermal decomposition of VCl3 at the same time causes that a VCl2-residue remains in the hot region. 相似文献