New development in RECEP (rapid estimation of correlation energy from partial charges) method

We analyze the feasibility of extremely rapid estimation of correlation energy from the HF-SCF charge distribution in closed-shell molecules. In Kristyanʹs previous work [Chem. Phys. 224 (1997) 33-51] a simple linear relationship using atomic correlations was developed in order to calculate correlation energy of molecules. This method has been further refined in this Letter. The proposed method is analyzed for 18 molecules and ions and the new results are compared to the B3LYP, CCSD and G2 results.