10 Å changes ∆E int by ∼ 0.1 kcal/mol but increases the requisite number of subsystem calculations from 2,534 to 3,496. Convergence behavior for the other three T4lysozyme systems is quite similar (see Fig. and Table ) and converged MBE(2) interaction energies are obtained using R cut = 8 Å in those cases as well.