[en] We used the distorted-wave approximation (DWA) and first-order many-body theory (FOMBT) for the calculation of integral cross sections (ICS's), differential cross sections (DCS's), and electron-impact coherence parameters (EICP's) for electron-impact excitation of neutral magnesium for several transitions. In the case of 3 ¹P excitation, we studied the basis-set dependence of the ICS's, DCS's, and EICP's, we investigated the effect of unitarization on these quantities, and we compared the DWA with FOMBT. We also studied the principal-quantum-number dependence of the EICP's for n ¹P (n=3,4,5,6) excitation