Nitrogen first ionization potential

It is worth pointing out, as do Capon and Wu69, Hickmott6/ and many others, that structural effects on the reactivity of enamines toward electrophiles are anticipated by a variety of physical properties of the enamines, including UV absorption frequencies, IR stretching frequencies, NMR chemical shifts and first ionization potentials. These properties in turn are influenced by the ability of the formal lone pair on the nitrogen to conjugate with the formal double bond, an ability which is modulated by both steric and electronic effects. 

These nitrogen bases are all oxidatively resistant and have first adiabatic ionization potentials close to the electron affinities of [Xe-F] [see reference (35) and Section IV], The estimated electron affinity of [XeF] is 10.9 eV and the first ionization potential of s-trifluorotriaz-ine, S-C3F3N3, is 11.50 eV, which led to the idea that the [S-C3F3N.2N-XeFT cation should exist. Reaction of the liquid triazine with [XeF]" [AsF(j] at room temperature, followed by removal of excess of the s-trifluorotriazine under vacuum, left a white powder that is stable indefinitely at room temperature, for which multinuclear magnetic resonance ( F, Xe) and Raman spectroscopic studies indicate clearly that it is the Xe-N-bonded cation [s-C3F3N2N-XeF]" (Fig. 8) (35). 

We performed the catalyzed disproportionation of 1,1,2,2-tetrachlorodimethyldisilane with different grafted nitrogenous donors. Apart from the steric influence their nucleophilicity plays an important role in the reaction. A re-electron system or a low first ionization potential of the donor does not seem to be a necessary condition for the disproportionation. 

P. Natalis and J. E. Collin, The first ionization potential of nitrogen dioxide, Chem. Phys. Letters 2, 79-82 (1968). 

There has been a great deal of interest in recent years in photoelectron spectroscopy (PES) of the isomeric A,B-diheteropentalenes containing sulfur, selenium and nitrogen. This technique has offered for the first time direct experimental evaluation of the ionization energies of the valence electrons. The sulfur- and selenium-containing heteroaromatics appear to be the class most investigated by PES. The ionization potentials of various A,B-diheteropentalenes, are presented in Table 3. 

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