 Effective nuclear charge

An orbital- and model-dependent parameter representing nuclear attraction after electronic screening. A screening construction writes $Z_{\mathrm{eff}}=Z-S$; a binding-energy construction requires an additional orbital-energy model.

Effective nuclear charge (often represented as \(Z_{\text{eff}}\)) refers to the net positive charge experienced by an electron in a multi-electron atom. While electrons are attracted to the positively charged nucleus, they also experience repulsion from other electrons. The effective nuclear charge accounts for both of these factors to give a more accurate measure of the attractive force an electron feels from the nucleus.