Electron aflinities

On ihe basis of the electron-oxidizing properties of the sequence of third transition series hexafluorides it has b n argued (see Barilett, N. An w. Chem., Int. Ed. Engl. 1968, 7, 433-439) that the electron aflinity increases approximately by 1 eV (23.06 kcal mol" ) for each unit increase in atomic number from WF lO PtF. With WFg (ref 24) and PtFg (ref 17) as fixed points, the increment becomes approximately 25 kcal mol" and this yields ,(ReF6) = 106 and ,(OsF ) = 130 kcal mol". ... 

For further discussion of electron aflinities, together with useful charts and graphs, see Chen. E. C. M. Wentworth, W. E. J. Chem. Educ. 1975, 52. 486. 

At this third-order level of approximation, the EP has been successfully applied to a large number of inorganic and organic molecules. The ionization potentials (Von Niessen, et a/., 1979) and electron aflinities (Simons, 1977) thus obtained are usually reliable to within 0.3 eV. 

Simpler Models of E(Z,N) in Terms of Ionization Potentials and Electron Aflinity. . 74... 

The chemical hardness of a metallic cluster can be expressed in terms of the ionization potential I and the electron aflinity A. In this paper we analyze the variation of I and A with cluster size, for the case of simple metals. The behavior of I and A shows interesting size effects, which manilcst themselves also in the behavior of the hardness. The chemical reactivity of metal clusters is sensitive to these size effects. 

Electron aflinity - The energy difference between the ground state of a gas-phase atom or molecule and the lowest state of the corresponding negative ion. 

The convention is to assign a negative value when energy is released and a positive value when energy is absorbed. Most elements have no affinity for an additional electron and thus have an electron aflinity equal to zero. We can represent the electron affinities of helium and chlorine as... 

II should be noted Ihat the proton aflinlies of aO of ihe irin aiive and dinegaihre anions are calculated by means of a Bom-Haber cycle. They are not erpenmemally accessAle apee these ions have no existence outside ofa stabilizing ory.sial environment—they would exothemacatly expel an electron (see Chapter 2). 

Several carbohydrate applications have been included in a review of micro-wave-assisted organic reactions, and a survey of chemical reagents in photo-aflinity labelling included the role of various base-labelled azido- and thio-nucleosides, sugar azide derivatives and p-benzoylbenzoate esters of nucleosides. A further review intitled Reverse Anomeric Effect Fact or Fiction refers to early evidence based on studies of glycosyl pyridinium and imidazolium salts. It concludes that its origin as an electronic effect is not supported by theory or experimental results. ... 

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