https://doi.org/10.1351/goldbook.E02015
The minimum work needed to extract electrons from the @F02341@ of a metal M across a surface carrying no net charge. It is equal to the sum of the potential energy and the kinetic @F02340@ taken with the reverse sign: \[\mathit{\Phi} ^{M} = -(V_{\text{e}}+ɛ_{\text{e}}^{F})\] where \(V_{\text{e}}\) is the potential energy for electrons in metals and \(\varepsilon_{\text{e}}^{\text{F}}\) is the @K03402@ of electrons at the @F02341@.