DLPNO-MP2 for periodic systems. I. Periodic boundary conditions

Area of Science:

• Computational Chemistry
• Quantum Chemistry
• Materials Science

Background:

• Accurate calculation of electronic correlation energy is crucial for understanding material properties.
• Existing methods for periodic systems often face computational challenges.
• Local pair natural orbital (PNO) methods have shown promise in molecular calculations.

Purpose of the Study:

• To extend the domain-based local pair natural orbital Møller-Plesset second-order perturbation theory (DLPNO-MP2) to periodic systems.
• To implement DLPNO-MP2 with Born-von Kármán (BvK) boundary conditions.
• To provide a computationally efficient and accurate method for electronic correlation in extended materials.

Main Methods:

• Development of DLPNO-MP2 with BvK boundary conditions using localized Wannier functions in a linear combination of atomic orbitals (LCAO) formalism.
• Formation of PNOs via a projected atomic orbital (PAO)-orbital specific virtual (OSV)-PNO cascade.
• Implementation of a chargeless and surface-dipole corrected local density fitting approach for stable lattice summations.

Main Results:

• The BvK-DLPNO-MP2 method demonstrates numerical stability and convergent lattice summations.
• DLPNO approximations are consistent with molecular DLPNO-MP2 and the Megacell-DLPNO-MP2 approach.
• The method shows smooth convergence to canonical correlation energy with PNO truncation.
• Reference MP2 correlation energies were computed for 2D and 3D periodic systems.

Conclusions:

• The developed BvK-DLPNO-MP2 method is a robust and accurate approach for calculating electronic correlation in periodic systems.
• This method extends the capabilities of local correlation methods to extended materials.
• The findings pave the way for more efficient and accurate theoretical studies of material properties.