Model calculations are described which predict the fraction of tetrahedral (sp3) versus graphitic (sp2) bonding in ion beam or plasma‐deposited amorphous carbon films on the basis of the preferential displacement ofsp2atoms. Displacement yields obtained from statictrimsimulations are used as input data for a simple analytical growing layer model of ion beam deposition. Thesp3/sp2ratio is found to increase with increasing carbon ion energy between 30 eV and 1 keV. Assuming equal probabilities for a free (implanted or displaced) atom to become trapped at eithersp2orsp3sites results insp3/sp2ratios between 1 and 3.5. More refined dynamic simulations withtridynconfirm the trends with slightly lowersp3/sp2ratios for ion beam or plasma deposition, also involving hydrogen. A decrease of thesp3/sp2ratio towards high energies cannot be explained by preferential displacement only, in contrast to proposals in recent literature.