  Electron affinity, electronegativity and electrophilicity of several neutral
atoms and their positive and negative ions are calculated at various levels of
theory using different basis sets in the gas phase as well as in the presence
of solvent and counterions. Electron affinity and electronegativity of all the
anions and dianions are negative in gas phase and accordingly the
electrophilicity is unexpectedly large vis-a-vis its quadratic definition. Many
of these trends get altered in case the effects of solvent and counterions are
taken into account.
