Electron impact collision strengths and transition rates for manganese ions of the Li I through F I isoelectronic sequence are calculated for transitions between levels of the configurations 2s22pk, 2s2pk+1, and 2pk+2. The excitation rate coefficients and transition rates obtained from these data are used to calculate level populations at temperatures of maximum abundance of the ions. The proton excitation rates for fine structure levels are also included in the level population calculations. The relative intensities of allowed lines are calculated and the calculated wavelengths are compared with the recent observations of the TFR group. The wavelengths of the forbidden and intersystem lines are also given and compared with the observations where available.