RAQET: Large-scale two-component relativistic quantum chemistry program package.

Area of Science:

• Computational Chemistry
• Quantum Mechanics
• Relativistic Physics

Background:

• Accurate quantum chemical calculations are crucial for understanding molecular properties, especially for systems containing heavy elements where relativistic effects become significant.
• Existing computational methods often face challenges in efficiently handling large molecules and complex relativistic formalisms.

Purpose of the Study:

• To introduce the Relativistic And Quantum Electronic Theory (RAQET) software package.
• To highlight RAQET's capabilities for large-scale, two-component relativistic quantum chemical calculations.
• To demonstrate the application of RAQET through various calculation examples.

Main Methods:

• Implementation of efficient schemes and algorithms for two-component relativistic quantum chemical calculations.
• Utilizing accurate relativistic formalisms including the two-component relativistic Hamiltonian.
• Integration of wavefunction theory, density functional theory, and core potential schemes.
• Customization of established non-relativistic quantum chemical techniques for relativistic applications.

Main Results:

• RAQET provides a robust platform for large-scale relativistic quantum chemical (QC) calculations.
• The software efficiently handles molecules containing heavy elements using accurate relativistic formalisms.
• Demonstrated capabilities through several illustrative calculation examples.

Conclusions:

• RAQET is a powerful new tool for computational chemists, particularly those working with heavy elements.
• The package facilitates accurate and efficient relativistic QC calculations, advancing the field of computational chemistry.
• RAQET's design enables broader accessibility to advanced relativistic quantum chemical methods.