An electrophilic atom is an electron-deficient atom in a molecule or ion. Use the following generalizations to identify most common types of electron-deficient atoms.
1. An atom that lacks an octet of valence electrons in one or more resonance forms is electron-deficient.
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2. A formally neutral aton bearing a partial positive charge but no lone pairs is an electron-defficient atom.
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see also nucleophilic atom, nucleophile, electrophile