Showing papers on "Valency published in 1975"
TL;DR: An allosteric model proposed previously for structure-function relations in hemoglobin is applied to the analysis of low- and high-spin valency hybrids to provide an interpretation of methemoglobin and its ligand replacement reactions and of the oxidation-reduction equilibrium of normal hemoglobin.
Abstract: An allosteric model proposed previously for structure-function relations in hemoglobin is applied to the analysis of low- and high-spin valency hybrids. By assuming that the low-spin oxidized chains have the tertiary structure of oxygenated chains while the high-spin oxidized chains have a tertiary structure intermediate between that of deoxygenated and oxygenated chains, the model parameters associated with the different valency hybrids can be obtained, and their equilibrium properties can be estimated. The hybrid results are used also to provide an interpretation of methemoglobin and its ligand replacement reactions and of the oxidation-reduction equilibrium of normal hemoglobin. For the various systems studied it is found that the effects of pH and 2,3-diphosphoglycerate are in agreement with the model.
33 citations
TL;DR: A simple model based on the resonant scattering theory can explain the first-order semiconductor-to-metal transition accompanied by a change of valency in SmS as mentioned in this paper.
31 citations
TL;DR: In this paper, a detailed Mossbauer study of 170Yb diluted in CaF2 has been performed on CaF 2 (170Yb) absorbers as well as on 170Tm sources, and an accurate determination of the nuclear factor, g ( 170 Yb, 84 keV ) = 0.334±0.002, has been derived from slow relaxation Hf splitting of cubic Yb3+.
16 citations
IBM1
TL;DR: In this paper, a smooth correlation between the determined chemisorption bond lengths, for O, S, Se and Te on Ni (001) and for sulphur on Ni(110) and Ni(111) as well as Pauling's resonating bond ionicity is demonstrated, when the latter are calculated with due regard for the coordination and valency saturation effects.
11 citations
TL;DR: In this article, the X-ray crystal structure analysis of cis-[PtPh2(Ph2PCH2PPh2)] suggests that the unusually low PtP coupling constant is a consequence of distortion of the valency angles at the platinum and phosphorus atoms; the restrictive geometry of the chelate ring does not effect the lengths of the metal ligand bonds.
10 citations
TL;DR: In this paper, the reaction of CrF 3 with oxides is compared, and the reactions observed being generally similar, with higher valency elements complete fluorine exchange did not always occur and oxyfluorides were formed.
6 citations
TL;DR: In this article, the cohesive energies, lattice constants and compressibilities for a number of metals are correlated with the ionic radii through second-order pseudo-potential theory, which yields reasonable results not only for simple metals of arbitrary valency, but for transition elements with no more than 5 d -electrons.
4 citations
TL;DR: The magnetic susceptibility of the dioxalatoplatinate acid (H 3 O) 1.6 [Pt(C 2 O 4 ) 2 ] n H 2 O, a mixed valency planar (MVP) compound with columnar structure and one-dimensional metallic conduction properties, has been measured in the temperature range 1.5 −300°K as mentioned in this paper.
4 citations
Patent•
18 Sep 1975
TL;DR: In this paper, a method for the polymerization of olefins using a catalyst in the form of a solid compound of a transition metal in which the transition metal is at least partially reduced to a valency state lower than the maximum valency states was proposed.
Abstract: A method for the polymerization of olefins using a catalyst in the form of a solid compound of a transition metal in which the transition metal is at least partially reduced to a valency state lower than the maximum valency state, with the transition metal compound being subjected prior to use to pre-activation by contact with magnesium and one or more halogenated hydrocarbons and one or more organo-metallic compounds of Groups II and III.
2 citations
TL;DR: In this article, the intermediate valence of SmS corresponding to extrema on the isobaric volume-temperature curves was derived, and a formula was derived which enables the intermediate value of the valence to be deduced.