The CCSD(T) is considered as the "gold-standard" method with a well-known limitation of its computational cost, pertaining to a non-linear scaling with system size (O(N 7 )). DLPNO-CCSD(T) is a local approximation to its canonical CCSD(T) methods, which maintains a high level of accuracy, 1kcal/mol, comparable to CCSD(T) while significantly lowering the computational cost.