Structure Dependence of Ionization Potentials

The assumption of small perturbation is clearly justified in the case of 

Stabilization energies (S) of the ground and ionized states of alkylethylenes referred to ethylene. derived from S,o nnai) using the observed changes in ionization potential (in e.v.) 

Higher ionization potentials in amines The large difference in ionization potential between the nitrogen lone pair and the electrons of alkyl groupings has made it comparatively easy 

Ionization Potentials of Methylamine (e.v.) by Electron Impact and Photoelectron Spectroscopy 

The second ionization potentials (e.v.) of aliphatic amines compared with first ionization potentials of the isoelectronic hydrocarbons 

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