Two or more molecular entities (atoms, molecules, or ions) are described as being isoelectronic with each other if they have the same number of electrons or a similar electron configuration and the same structure (number and connectivity of atoms), regardless of the nature of the elements involved.

Two or more molecular entities (atoms, molecules, or ions) are described as being isoelectronic with each other if they have the same number of electrons or a similar electron configuration and the same structure (number and connectivity of atoms), regardless of the nature of the elements involved.