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Alexey N. Egorochkin Olga V. Kuznetsova Nadiya M. Khamaletdinova Lada G. Domratcheva-Lvova Georgy A. Domrachev 《Journal of organometallic chemistry》2009,694(9-10):1447-1452
The literature date on substituent influence on the carbonyl stretching frequencies (ν), CO stretching force constants (k), as well as 13C NMR carbonyl chemical shifts (δ) have been analyzed for 19 series of the transition metal carbonyl complexes. It was established for the first time that the ν, k and δ values depend not only on the inductive and resonance effects but also on the polarizability of substituents. The polarizability contribution ranges up to 37%. 相似文献
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一、TheProblem .Letf(x) =ax2 bx c ax2 px q,wherea >0 ,b2 - 4ac≤ 0andp2 - 4aq≤ 0 .OurProblemis“Whetherdoesminx∈Rf(x)exis?Moreover ,,ifminx∈Rf(x)exists,thenminx∈Rf(x)=?andinthiscasex =?” .Naturally ,weknowthatminx∈Rf(x)existsfromtheknowledgeofmathematicalanalysis.Also,wecangivethe… 相似文献
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Egorochkin AN Kuznetsova OV Khamaletdinova NM Domratcheva-Lvova LG 《Magnetic resonance in chemistry : MRC》2011,49(4):175-183
The literature data on substituent influence on the g factors, hyperfine coupling (hfc) constants (a) of the EPR signals and the spin densities (ρ) have been analyzed for 25 series of the organic radical cations and radical anions as well as of the transition metal complexes. The g, a, and ρ values were first established to depend not only on the inductive and resonance effects but also on the polarizability of substituents which can be characterized by the σ(α) constants. The polarizability effect is caused by the partial charge on the radical center. This effect consists in an electrostatic attraction between the charge and the dipole moments induced by this charge in the substituents. The polarizability contribution ranges up to 92%. 相似文献
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The synthesis and characterization of new metal-free (9) and metal-containing (Zn, Ni or Cu 10, 11, 12) derivatives of a symmetrically octasubstituted phthalocyanine derived from 21,22-dicyano-2,3,5,6,8,9,11,12,15,17,18,25,26,28-tetradecahydro[1,4,7,12] benzodioxadithiacyclotetradeceno[6,7-b][1,4,7,10,13]benzopentaoxacyclopentadecene (7), which was synthesized in a multi-step reaction sequence, have been described. The novel compouds have been characterized by a combination of elemental analysis, 1H and 13C NMR, IR, UV–vis and MS spectral data. 相似文献
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