Ground States for Metals from Converged Coupled Cluster Calculations

Area of Science:

• Computational materials science
• Quantum chemistry

Background:

• Predicting material properties requires accurate many-electron correlation methods.
• Achieving precise ground-state properties for bulk metals remains a challenge.

Purpose of the Study:

• To propose a novel scheme for calculating the thermodynamic limit of ground-state energy in metals using coupled cluster theory.
• To demonstrate the suitability of coupled cluster theory for metallic materials, particularly in surface science.

Main Methods:

• Developed a novel scheme within coupled cluster theory to approximate the thermodynamic limit.
• Exploited the weak coupling between long-range and short-range correlation energy contributions.
• Calculated surface energies for aluminum and platinum (111).

Main Results:

• Demonstrated convergence with respect to finite-size effects, basis-set size, and coupled cluster expansion.
• Achieved excellent agreement between calculated and experimental data for surface energies.
• Showcased the weak coupling enabling controllable restriction of long-range correlation contributions.

Conclusions:

• The proposed coupled cluster scheme is well-suited for modeling metallic materials, especially in surface science.
• This work enables more efficient coupled cluster calculations for larger systems.
• Facilitates broader theoretical utilization in realistic metallic material models.