[en] Radiation emission from thin solid targets irradiated by short-intense laser pulses has been re-examined. Free electrons in the material are driven by the applied external radiation field and harmonics are generated by the electronic response to the crystal lattice force. Recent work on this phenomenon has drawn attention to a flat spectral profile featured by a sudden cut-off at high harmonic order. In the present work we report a number of effects that may in practice have a bearing on the emission. A model was modified by introducing a more general expression for the lattice force that by sharpening or by smoothing the potential in turns allow the strength of the electronic perturbation to be varied. Results from the computed emission reported here show that the pulse shape and the intensity of the laser light may modify the spectral characteristics. For infinite plane waves the obtained emission spectra are in accordance with a recent theoretical model. (Author)