[en] Isotope ratio enhancement factor and isotope selectivity of ²³⁵U in five excitation schemes (I: 0→10069 cm^-1 →IP, II: 0 →10081 cm^-1 →IP, III: 0 →25349 cm^-1→ IP, IV: 0→28650 cm^-1 →IP, V: 0→16900 cm^-1 →34659 cm^-1 →IP), were computed by a spectral simulation approach. The effect of laser bandwidth and Doppler width on the isotope ratio enhancement factor and isotope selectivity of ²³⁵U has been studied. The photoionization scheme V gives the highest isotope ratio enhancement factor. The main factors which effect the separation possibility are the isotope shift and the relative intensity of the transitions between hyperfine levels. The isotope ratio enhancement factor decreases exponentially by increasing the Doppler width and the laser bandwidth, where the effect of Doppler width is much greater than the effect of the laser bandwidth. (author)