Free clusters that cool by evaporation will have a defined distributio
n of internal energies in spite of lack of contact with a heat bath. T
his distribution has previously been considered for small clusters. He
re we present results valid for large clusters. A simple Gaussian shap
e is predicted in this regime and we calculate the mean and variance o
f the distribution. The limit of validity of previous and present work
is discussed. The analytical results are compared to numerical simula
tions.