  Strong ($10^{10}$ V/m) electric fields capable of inducing atomic
bond-breaking represent a powerful tool for surface chemistry. However, their
exact effects are difficult to predict due to a lack of suitable tools to probe
their associated atomic-scale mechanisms. Here we introduce a generalized
dipole correction for charged repeated-slab models that controls the electric
field on both sides of the slab, thereby enabling direct theoretical treatment
of field-induced bond-breaking events. As a prototype application, we consider
field evaporation from a kinked W surface. We reveal two qualitatively
different desorption mechanisms that can be selected by the magnitude of the
applied field.
