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91.
络合物晶体的电子吸收光谱作为研究晶体的电子结构的基础内容,很早以前就得到人们注意,虽然对Cu~(2+)、Ni~(2+)等络合物电子光谱的能级的经验指认已是一项较为成熟的工作,但对吸收光谱的系统的理论计算和定量解释在以前的文献中尚不多见.近年来,我们对多种晶体的电子吸收光谱进行了定量的解释,结果表明理论计算值总是能很好地符合于实验测定值。一般说来,吸收峰位的波数误差在8%以内. 早在本世纪四十年代就奠定了乙二胺四乙酸(EDTA)在分析化学中的应用基础。 相似文献
92.
Karl Hassler 《Monatshefte für Chemie / Chemical Monthly》1982,113(4):421-425
A simple preparation of the title compounds is achieved by reacting Na3P/K3P with stoichiometric mixtures of chlorotriphenylsilane and chlorotrimethylsilane.31P- and29Si-NMR-Data as well as Ir and Raman spectra of the compounds are reported. 相似文献
93.
A. V. Ivanov P. A. Svinareva I. V. Zhukov L. G. Tomilova N. S. Zefirov 《Russian Chemical Bulletin》2006,55(2):281-286
A series of the earlier unknown diphthalocyanine complexes of rare-earth metals based on 4,5-isopropylidenedioxyphthalonitrile
were prepared. Their compositions and yields depend on the radius of the complexing ion. The synthesized compounds were studied
by spectroscopy and electrochemical methods. The redox potentials of the complexes studied change nonlinearly with a decrease
in the lanthanide ion radius.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 274—279, February, 2006. 相似文献
94.
赖氨酸-Ag反应机理的研究 总被引:5,自引:0,他引:5
The interaction of silver(Ⅰ) ion with lysine has been investigated by UV-Vis, fluorescent spectra and electrophoresis method. The effect of pH medium and multicomponent concentration on interaction of lysine-silver has also been studied. Lysine-silver system showed maximum absorbance at 239 nm and 448 nm. Lysine showed fluorescence. The fluorescence excitation wavelength was about 356.6 nm (fluorescence emission wavelength was about 438.6 nm). When the reaction of silver(Ⅰ) ion with lysine happened, fluorescence was quenching. Lysine-silver system carried negative charge, and the electrokinetic potential of double electrode layer was -2.35×10-4 V. 相似文献
95.
配体形状对多吡啶铜(Ⅱ)配合物与DNA作用的影响 总被引:11,自引:0,他引:11
合成了一系列含有平面配体的Cu(Ⅱ)多吡啶配合物[Cu(IP)2]2+、[Cu(PIP)2]2+、[Cu(DPPZ)2]2+和[Cu(HPIP)2]2+,用吸收光谱、CD光谱和粘度等方法研究了这些配合物与小牛胸腺DNA的作用。结果表明配体上的取代基及配体的平面性对这些四面体配合物与DNA的结合强弱产生一定的影响。[Cu(DPPZ)2]2+与DNA的结合较强,而[Cu(HPIP)2]2+与DNA的结合较弱。CD光谱显示配合物[Cu(DPPZ)2]2+、[Cu(PIP)2]2+和[Cu(HPIP)2]2+的加入会导致DNA的CD光谱减弱。而[Cu(IP)2]2+的加入则会使DNA的CD光谱增强。同时,[Cu(IP)2]2+与DNA结合后,还会引起一定程度的DNA构型转换,即DNA从B型转换成Z型。 相似文献
96.
V. A. Mamedov A. A. Kalinin V. V. Yanilkin N. V. Nastapova V. I. Morozov A. A. Balandina A. T. Gubaidullin O. G. Isaikina A. V. Chernova Sh. K. Latypov I. A. Litvinov 《Russian Chemical Bulletin》2007,56(10):2060-2073
The oxidative dehydrocyclization of the 3-(indolizin-2′-yl)-2-oxoquinoxaline monopodand performed either electrochemically
or under the action of molecular iodine affords new redox-active heterocyclophane consisting of the redox-switchable biindolizine
fragment combined with the polyether-bridged π-deficient quinoxaline systems. The single-crystal X-ray diffraction study showed
that the trioxaundecane chain of heterocyclophane adopts an extended conformation, and one of the phenyl substituents of the
molecule closes the pseudocavity formed by the spacer from one of the sides. The cyclic voltammetric study of heterocyclophane
in MeCN and DMF showed the three-step oxidation of the indolizine fragments accompanied by the single-electron transfer in
each step. The first and third steps are reversible, and the second step is irreversible. The oxidation at potentials of the
first peak gives rise to stable radical cations detected by the ESR method (g = 2.0024, a
2N = 0.26 mT).
Dedicated to Professor E. A. Berdnikov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1991–2003, October, 2007. 相似文献
97.
Anju Midha Rajender D. Verma K. Brown R. V. Parish 《Monatshefte für Chemie / Chemical Monthly》1983,114(6-7):661-667
Mixed dialkytin(IV) trifluoroacetates,Me EtSn(O2CCF3)2,Et Pr
n
Sn(O2CCF3)2 andPr
n
Bu
n
Sn(O2CCF3)2 have been prepared by metathetical reactions of the corresponding dialkyltin(IV) chlorides with silver trifluoroacetate in CH2Cl2. They are monomeric in benzene and nonconducting inMeNO2 andMeCN. Bidentate trifluoroacetate groups are indicated by their IR spectra.Mössbauer spectra confirmtrans-arrangement of theR-Sn-R moiety.1H,19F NMR and mass spectra are also discussed.
Gemischte Dialkylzinn(IV)-trifluoracetate
Zusammenfassung Die gemischten Dialkylzinn(IV)-trifluoroacetateMe EtSn(O2CCF3)2,Et Pr n Sn(O2CCF3)2 undPr n Bu n Sn(O2CCF3)2 wurden über Metathese-Reaktionen der entsprechenden Dialkylzinn(IV)-chloride mit Silbertrifluoracetat in CH2Cl2 dargestellt. Sie sind monomer in Benzol und nichtleitend inMeNO2 undMeCN. Die IR-Spektren zeigen zweizähnige Trifluoracetat-Gruppen an. DieMössbauer-Spektren bestätigen dietrans-Anordnung derR-Sn-R-Einheit. Die1H-,19F-NMR und die Massenspektren werden ebenfalls diskutiert.相似文献
98.
L. A. Chekulaeva I. A. Garbuzova V. V. Gavrilenko L. B. Danilevskaya V. A. Kotel'nikov 《Russian Chemical Bulletin》1996,45(9):2199-2202
Alkali metal salts of acrylamide C3H4NOM (M = Li, Na, and K) were synthesized for the first time by metallation of acrylamide with alkali metals, their alkyl derivatives, or hydrides. The structures of the compounds synthesized were studied by Raman and IR spectroscopy. Based on the results obtained, an ionic structure was proposed for the salts. The salts were tested as initiators of the anionic polymerization of acrylamide. The catalytic activity of C3H4NOM in the polymerization of acrylamide is not lower than that of the well known catalyst, KOBu1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2316–2319, September, 1996. 相似文献
99.
Contributions to the Chemistry of Transition Metal Alkyl Compounds. 59. Cyclopentadienyl-2-(dimethylaminomethyl)ferrocenyl Compounds of Early 3 d-Elements Compounds of the type (C5H5)2M(FcN) (M = Sc ( 1 ), Ti ( 2 ), V ( 3 ), Cr ( 4 ); FcN = 2-dimethylaminomethyl)ferrocenyl group), and (C5H5)M(FcN)2 (M = Ti ( 5 ), Cr ( 6 ) were synthesized and investigated. A detailled characterization with respect to the existence of chelate structures was realized by the uv-vis, 1H-n.m.r. spectroscopic measurements and determination of magnetic moments. 相似文献
100.
L. A. Leites A. V. Zabula S. S. Bukalov P. S. Koroteev O. S. Maslennikova M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2005,54(5):1117-1120
The vibrational spectra of tetravalent metal halides (M = Si, Ge, Sn) and the corresponding dihalocarbene analogs MIIHal2, obtained by the authors, and the relevant published data are compared. The spectra of the MIIHal2 species exhibit inversion of the M-Hal stretching frequencies (νs(MIIHal) > ν as(MIIHal)). This can be used for analytical purposes and allows one to distinguish between the spectra of the MIV and MII halides. The IR and Raman spectra of the complexes of dihalogermylenes and -stannylenes with triphenylphosphine and 1,4-dioxane
also exhibit inversion of the ν(MHal) stretching frequencies. This confirms the conclusion drawn earlier based on the analysis
of the geometric parameters and reactivities of the complexes in question that the divalent state of the M atom in these species
is retained.
Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday.
__________
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1089–1092, May, 2005. 相似文献