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521.
A cobalt σ-alkane complex, [Co(Cy2P(CH2)4PCy2)(norbornane)][BArF4], was synthesized by a single-crystal to single-crystal solid/gas hydrogenation from a norbornadiene precursor, and its structure was determined by X-ray crystallography. Magnetic data show this complex to be a triplet. Periodic DFT and electronic structure analyses revealed weak C−H→Co σ-interactions, augmented by dispersive stabilization between the alkane ligand and the anion microenvironment. The calculations are most consistent with a η11-alkane binding mode.  相似文献   
522.
523.
从心理活动功能角度建构人际沟通能力沟通技能、沟通认知和沟通倾向三元结构.采用国内学者编制的测量量表,运用探索性因子分析,筛选出了人际沟通能力言语表达、非言语表达、倾听、沟通认知和沟通倾向5个因子,可解释总体方差的74.23%.通过因子分析筛选出沟通技能的言语表达、非言语表达和倾听三项技能特质,人际沟通能力三元结构在人际沟通能力问卷测量中得以证实.  相似文献   
524.
A 3-amino-functionalized phosphabenzene (phosphinine) has been synthesized and structurally characterized. The pyramidalized nitrogen atom of the dimethylamino substituent indicates only a weak interaction between the lone pair of the nitrogen atom and the aromatic phosphorus heterocycle, resulting in somewhat basic character. It turned out that the amino group can indeed be protonated by HCl. In contrast to pyridines, however, the phosphabenzene-ammonium salt undergoes a selective ring contraction to form a hydroxylphospholene oxide in the presence of additional water. Based on deuterium labeling experiments and quantum chemical calculations, a rational mechanism for this hitherto unknown conversion is proposed.  相似文献   
525.
[K{Al(NONDipp)}]2 (NONDipp=[O(SiMe2NDipp)2]2−, Dipp=2,6-iPr2C6H3) reacts with CS2 to afford the trithiocarbonate species [K(OEt2)][Al(NONDipp)(CS3)] 1 or the ethenetetrathiolate complex, [K{Al(NONDipp)(S2C)}]2 [ 3 ]2. The dimeric alumoxane [K{Al(NONDipp)(O)}]2 reacts with carbon monoxide to afford the oxygen analogue of 3 , [K{Al(NONDipp)(O2C)}]2 [ 4 ]2 containing the hitherto unknown ethenetetraolate ligand, [C2O4]4−.  相似文献   
526.
Compounds (I), C14H20N2O4S, and (II), C12H14N2O3S2, are two minor products of the same reaction. Both structures contain identical ester functionalities in similar orientations. Both independent mol­ecules of (I) contain an ethoxy­carbo­thio­yl­amine moiety, whilst (II) possesses a novel exocyclic thione system fused with a pyridine ring.  相似文献   
527.
The dynamics of an atom coupling to a quantized cavity field have been studied. The atom is treated as a two-level system with a spontaneous emission rate. The transition probabilities have been given for both adiabatic and non-adiabatic situations. For a special Λ-type atom with dark state, the problem of momentum transfer is discussed in details. The influence of spontaneous emission on validity of the adiabatic approximation is also discussed.  相似文献   
528.
The dynamics of electric-field-induced lattice distortions and phase transitions in the BPI, BPII and BPIII (fog) phases of blue-phase mixtures, which include low-molar-mass and/or polymeric components, have been studied. Several electric-field-induced effects have been observed in the blue phases, and the electro-optic characteristics of the driven and non-driven responses of each are considered. Anomalous behaviour in BPIII, where driven response times were measured to be slower than the relaxation responses, is described and considered with respect to relaxation processes previously observed in BPII. Finally, we present data for a mixture containing 40 per cent by weight of a side-chain-polymer liquid crystal. In this case only BPI was observed, and it appears that the increased viscosity had little effect on the response times of the system. These data are discussed.  相似文献   
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