  The gap in semiconductor nanocrystallites has been extensively studied both
theoretically and experimentally over the last two decades. We have compared a
recent ``state-of-the-art'' theoretical calculation with a recent
``state-of-the-art'' experimental observation of the gap in Si nanocrystallite.
We find that the two are in substantial disagreement, with the disagreement
being more pronounced at smaller sizes. Theoretical calculations appear to
over-estimate the gap. Recognizing that the experimental observations are for a
distribution of crystallite sizes, we proffer a phenomenological model to
reconcile the theory with the experiment. We suggest that similar
considerations must dictate comparisons between the theory and experiment
vis-a-vis other properties such as radiative rate, decay constant, absorption
coefficient, etc.
