Finite-temperature-based linear-scaling divide-and-conquer self-consistent field method for static electron correlation systems

In this letter, we developed divide-and-conquer-based self-consistent-field methods with a finite-temperature (FT) scheme, denoted as FT-DC-SCF. The FT scheme can approximately involve the static correlation effect observed in bond-breaking reactions, double bond rotations, diradicals, and conjugated polymers within small additional computational costs. Test calculations of polyene, water cluster, diamond, graphene, magnesium oxide, and titanium demonstrate the high accuracy and efficiency of the developed FT-DC-SCF method. Furthermore, FT-DC-SCF was applied to the singlet-triplet energy gap and double bond rotation.