Covalency
Mostrando 1-6 de 6 artigos, teses e dissertações.
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1. O plÃsmon da regiÃo de recobrimento da ligaÃÃo quÃmica como ferramenta para caracterizaÃÃo de materiais
Important issues can be raised about the possibility of relations between macroscopic properties of materials and concepts, introduced recently, of the chemical bond overlap polarizability (PR) and the concept of ionic specific valence (VIE). A proposal in which the overlap region of chemical bond is considered as a âplasmon‐likeâ charge distribution
Publicado em: 2009
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2. Effect of Nd3 + concentration on the physical and absorption properties of sodium-lead-borate glasses
The effect of increasing the rare earth ion concentration on the physical and spectroscopic properties of Nd3 + doped sodium-lead-borate glasses have been studied for the compositions (10-x) Na2O-30PbO-60B2O3-xNd2O3, where x = 1.00, 1.25, 1.50, 1.75 and 2.00 mol %. Optical band gaps, cut-off wavelengths and various spectroscopic parameters (E¹, E², E³, F2
Brazilian Journal of Physics. Publicado em: 2007-12
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3. Compostos de adição entre iodetos de itrio e lantanídeos(III) e a N,N,N\ ,N\ - tetrametilmalonamida / N, N, N\ , N\ - tetramethylmalonamide adducts of lanthanide iodides
Addition compounds of formula Lni3.xTMMA (x = 5 for Ln = La, Ce and x = 4 for Ln = Pr - Lu, Y) were prepared by reaction of N,N.N\ ,N\ -tetramethylmalonamide (TMMA) and lanthanide iodides in acetone. The crystalline adducts present the same, but fainter colors of the corresponding lanthanide ions; they are in general practically not hygroscopic and melt with
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 22/02/1979
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4. On the electronic nature of low-barrier hydrogen bonds in enzymatic reactions
The electronic nature of low-barrier hydrogen bonds (LBHBs) in enzymatic reactions is discussed based on combined low temperature neutron and x-ray diffraction experiments and on high level ab initio calculations by using the model substrate benzoylacetone. This molecule has a LBHB, as the intramolecular hydrogen bond is described by a double-well potential
The National Academy of Sciences.
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5. Electron Spin Resonance Studies of Carbonic Anhydrase: Transition Metal Ions and Spin-Labeled Sulfonamides*
Electron spin resonance (esr) spectra of Cu(II) and Co(II) carbonic anhydrase, and a spin-labeled sulfonamide complex of the Zn(II) enzyme, are reported. The coordination geometry of Cu(II) bound in the enzyme appears to have approximately axial symmetry. Esr spectra of enzyme complexes with metal-binding anions also show axial symmetry and greater covalency
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6. Syncatalytic conformational changes in aspartate aminotransferase determined by hydrogen-deuterium exchange.
Catalysis-linked conformational transitions of aspartate aminotransferase (cytosolic isoenzyme from pig heart; L-aspartate:2-oxoglutarate aminotransferase, EC 2.6.1.1) have been probed by infrared spectrophotometric measurement of hydrogen-deuterium exchange. In the unliganded pyridoxal form of the enzyme at pH 6.0 and 20 degrees, 43% of the total 411 peptid