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11.
An optical-optical double-resonance technique has been applied to study the D(0u+) ion-pair state of Br2 in a one-photon resonant three-photon absorption. The OODR transition proceeds through the high vibrational level of the B3Π(0u+) state, which compromises a large Franck-Condon shift required for the excitation of Br2 from the X1Σg+ state to the D(0u+) state. Dunham parameters of the D(0u+) state, based on a global least-squares fit of 407 transitions (v′ = 0–16, J′ = 17–115), are Y00 = 49928.443(41), Y10 = 134.467(19), Y20 = ?8.71(27) × 10?2, Y30 = ?3.36(10) × 10?3, Y01 = 4.2382(15) × 10?2, Y11 = ?1.061(36) × 10?4, Y21 = ?2.00(27) × 10?6, and Y02 = ?1.93(11) × 10?8 for 79Br2 (all in cm?1, and 3σ in parentheses). The single rovibronic fluorescence spectrum of the D(0u+) state shows a transition terminating on the X1Σg+ ground state, and establishes the absolute v′ numbering on the basis of the Franck-Condon factor calculations. The v′ = 2 and 3 levels of the D(0u+) state are strongly perturbed due to the heterogeneous interaction with the 1u state correlating with the same ionic products of the D(0u+) state at the dissociation limit, Br?(1S) + Br+(3P2).  相似文献   
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Anodic oxidation in acetic acid of polycyclic cyclopropanes, namely tricyclene, cyclofenchene, and longicyclene, followed by hydrolysis brought about stereo- and regioselective formation of the corresponding homoallylic alcohols as the main product in good yields.  相似文献   
13.
Considerable amounts of benzene were formed by heating triphenylphosphine complexes of transition metals in several types of organic compounds, especially in amines; in the case of a tributylphosphine complex, n-butane was detected. In the reactions with indoline, tetrahydroquinoline or dioxane, the hydrogen consumed for the hydrogenolysis was proved to arise from the amines or the ether.  相似文献   
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Oxide ion conductivity in La(2)GeO(5)-based oxide was investigated and it was found that La-deficient La(2)GeO(5) exhibits oxide ion conductivity over a wide range of oxygen partial pressure. The crystal structure of La(2)GeO(5) was estimated to be monoclinic with P2(1)/c space group. Conductivity increased with increasing the amount of La deficiency and the maximum value was attained at x = 0.39 in La(2 - x)GeO(5 - delta). The oxide ion transport number in La(2)GeO(5)-based oxide was estimated to be unity by the electromotive force measurement in H(2)-O(2) and N(2)-O(2) gas concentration cells. At a temperature higher than 1000 K, the oxide ion conductivity of La(1.61)GeO(5 - delta) was almost the same as that of La(0.9)Sr(0.1)Ga(0.8)Mg(0.2)O(3 - delta) or Ce(0.85)Gd(0.15)O(2 - delta), which are well-known fast oxide ion conductors. On the other hand, a change in the activation energy for oxide ion conductivity was observed at 973 K, and at intermediate temperature, the oxide ion conductivity of La(1.61)GeO(5 - delta) became much smaller than that of these well-known fast oxide ion conductors. The change in the activation energy of the oxide ion conductivity seems to be caused by a change in the local oxygen vacancy structure. However, doping a small amount of Sr for La in La(2)GeO(5) was effective to stabilize the high-temperature crystal structure to low temperature. Consequently, doping a small amount of Sr increases the oxide ion conductivity of La(2)GeO(5)-based oxide at low temperature.  相似文献   
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Various types of lipid membrane-incorporated C60 with high C60 concentrations can be prepared easily in several hours using the C60 exchange method and the photocleaving activity of cationic lipid membrane-incorporated C60 was appreciably higher than that of the C60.gamma-CDx complex.  相似文献   
19.
Electronic spectra of a homo-molecular dimer cation, (C6H5CN)2 +, are measured by photodissociation spectroscopy in the gas phase. Broad features appeared in the 450–650 nm region are characteristic of π3 → πCN transitions of the C6H5CN+ chromophore. No intense band is observed in the 650–1300 nm region, where other aromatic dimer cations usually show charge resonance bands. Two component molecules of (C6H5CN)2 + cannot take a parallel sandwich configuration suitable for the resonance interaction, because of geometrical constraints due to other stronger interactions.  相似文献   
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The S2 state fluorescence of Zn(II)tetraphenylporphin has been studied by using two-photon absorption and optical—optical double-resonance techniques. The main process to populate the S2 state was found to be a stepwise two-photon absorption to the Snstate through the S1 state. The large absorption cross section of the Sn ← S1 transition (6.8 × 10?16 cm2 molecule?1) at 540 nm suggests that there exists a higher excited singlet state of gerade parity.  相似文献   
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