Error analysis of incremental electron correlation calculations and applications to clusters and potential energy surfaces

An analysis of the propagation of errors in the incremental expansion of the correlation energy is presented. The potential accuracy of the incremental scheme is demonstrated explicitly for cluster compounds. The errors due to the truncation of the series at low order can be controlled in a systematic way and the error in the total correlation energy can be kept lower than 1 kcal/mol with respect to the canonical CCSD calculation. Finally, the performance of the incremental scheme in calculating potential energy surfaces is demonstrated.