Konstantinos D. Vogiatzis introduces a novel approximate coupled-cluster scheme that estimates the coupled-cluster singles-and-doubles with perturbative triples (CCSD(T)) energy at the basis set limit. Recognized as the 'gold standard' in electronic structure theory, the CCSD(T) method is limited by its high computational demands for achieving accuracy. Vogiatzis's new method overcomes this challenge by incorporating terms from interference-corrected explicitly-correlated second-order perturbation theory. The "CCSD(T)-INT-F12" method achieves the desired accuracy of CCSD(T) in significantly less time. The theoretical foundation of this method is explored, along with its computational efficiency and accuracy. Its performance is validated in two areas: the calculation of atomization energies and reaction barrier heights, emphasizing the role of interference corrections, and the assessment of noncovalent interactions. The method demonstrates high accuracy in calculating interaction energies, as evidenced by impressive results for the S22 test set. Additionally, it is applied to investigate noncovalent interactions, specifically the non-classical amino NH.π hydrogen bond and hydrogen adsorption in metal-organic frameworks (MOFs) with open metal sites. Notably, the strength of the interaction suggests potential applications for these porous materials as hydrogen carriers.
