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本文合成了2个新型Cu(Ⅱ)配合物:[Cu2(L1)2Cl4]L1(1)和[Cu(L2)2(NO3)2(H2O)](2),其中L1为3,6-二(苯并三唑-1-)哒嗪,L3为3-(1,2,4-三氮唑-1-)-6-氯哒嗪.配合物1的晶体属于三斜晶系,P1-空间群.铜离子与3个氯原子和配体的2个氮原子形成五配位的四角锥构型,2个氯原子以μ-2方式桥联2个中心铜原子.在配合物1的晶胞中1个游离配体未参与配位.配合物2的晶体属于单斜晶系,C2/c空间群.铜原子处于五配位四角锥配位环境中.分子间氢键将2的分子结构延伸为一维链、二维网状结构.并通过分子间的π-π堆积作用进一步使配合物构型发展成三维拓扑结构.应用邻苯三酚自氧化法对本文所涉及的化合物进行了清除自由基活性测试,结果表明:这2个配体都具有较好的活性. 相似文献
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A. I. Onipko 《Molecular Crystals and Liquid Crystals》2013,570(3-4):235-247
The energy spectrum and the spectrum of light absorption by impurity crystal are studied taking into account a nondiagonal perturbation caused by an impurity molecule. The effect of the intermolecular guest-host interaction on the conditions of existence of in-band resonance states is analysed and the frequency dependence of the half-width and the intensity of the resonance impurity absorption peak is obtained. The band absorption spectrum is calculated in the nearest-neighbour-approximation for one-dimensional and three-dimensional impurity crystals. 相似文献
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The temperature dependence of the cholesteric pitch of the chiral ester 4-n-hexyloxyphenyl-4'-(2”-methylbutyl)biphenyl-4-carboxylate has been measured in detail using the method of selective reflection. This compound has a cholesteric to smectic-C transition at 79°C. Because of the first-order nature of the transition, the pretransitional unwinding of the pitch is considerably less pronounced than that in cholesteryl esters near the smectic-A transition. The wavelength of maximum reflection increases from 440 nm at 110°C to 560 nm at the transition. When fitted to a power-law temperature dependence, the data imply an exponent of 0.82 ± 0.15, which is consistent with de Gennes’ theory in the meanfield approximation. 相似文献
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I. B. Dzvinchuk A. M. Nesterenko M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2008,44(2):190-196
Treatment of 1,4-diaryl-2-(1H-benzimidazol-2-yl)butane-1,4-diones with hydrazine gives the previously unknown 2-(3,6-diaryl-2,5-dihydropyridazin-4-yl)-1H-benzimidazoles
which are aromatized by oxidation with nitrous acid to give 2-[3,6-diarylpyridazin-4-yl]-1H-benzimidazoles.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 252–259, February, 2008. 相似文献
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Doo‐Sik Ahn Kyo‐Won Choi Dr. Sun Jong Baek Dr. Young S. Choi Prof. Sungyul Lee Prof. Heechol Choi Dr. Kyoung Koo Baeck Prof. Sang Kyu Kim Prof. 《Chemphyschem》2008,9(11):1610-1616
The molecular structure of pyridazine in the first electronically excited state (S1) is deduced from the combined use of resonance‐enhanced two‐photon ionization and mass‐analyzed threshold ionization spectroscopic methods. The equation‐of‐motion coupled‐cluster single and double (EOM–CCSD) calculation gives the distorted planar geometry for the most stable structure of the S1 pyridazine. The symmetry constraint of C2v is relaxed to that of Cs, and consequently many in‐plane vibrational modes are found to be optically active in both S1–S0 and D0–S1 excitation spectra, being appropriately assigned from the comparison of their frequencies with ab initio values. This indicates that the S1–S0 excitation is partially localized, and provides an alternative explanation for the long‐standing spectroscopic puzzle in S1 pyridazine. 相似文献