The ab-initio density matrix renormalization group in practice.

Area of Science:

• Quantum Chemistry
• Computational Chemistry
• Condensed Matter Physics

Background:

• The ab-initio density matrix renormalization group (DMRG) is a versatile computational tool.
• Its application in quantum chemistry is of significant interest.
• Understanding its capabilities and limitations is crucial for practical use.

Purpose of the Study:

• To evaluate the density matrix renormalization group (DMRG) from a quantum chemistry user's perspective.
• To identify suitable problems and system sizes for DMRG calculations.
• To assess achievable accuracies and computational costs for various molecules.

Main Methods:

• Application of ab-initio density matrix renormalization group (DMRG).
• Examination of a diverse benchmark set of molecules.
• Analysis of π-electron systems, main-group and transition metal dimers, and organometallic compounds (Mn-oxo-salen, Fe-porphine).

Main Results:

• The study provides insights into the types of quantum chemistry problems amenable to DMRG.
• It addresses the scalability of DMRG for treating larger systems at practical costs.
• Accuracies and computational difficulties associated with different molecular systems are discussed.

Conclusions:

• The density matrix renormalization group (DMRG) is a practical tool for specific quantum chemistry challenges.
• The findings guide users in selecting appropriate problems and interpreting computational results.
• This work demonstrates the utility of DMRG in computational chemistry research.