Global Elucidation of Self-Consistent Field Solution Space Using Basin Hopping.

Area of Science:

• Computational Chemistry
• Quantum Mechanics
• Electronic Structure Theory

Background:

• Accurate self-consistent field (SCF) solutions are fundamental for computational chemistry.
• Exploring the landscape of SCF solutions is challenging but necessary for developing robust computational methods.

Purpose of the Study:

• To develop and implement a stochastic algorithm for the global elucidation of SCF solutions.
• To provide a reliable method for finding diverse SCF solutions for use as reference wavefunctions.

Main Methods:

• Combines basin-hopping global optimization with a Lie algebraic approach.
• Linearizes the SCF solution space while preserving spin-symmetry properties.
• Tested on C2H4, benzene, and NO2 using various basis sets.

Main Results:

• Successfully demonstrated the algorithm's performance on a model system (C2H4).
• Identified low-lying SCF solutions for benzene and NO2 with polarized double-zeta and triple-zeta basis sets.
• Examined the properties of the identified SCF solutions.

Conclusions:

• The developed stochastic approach offers an effective strategy for global SCF solution elucidation.
• This method enhances the reliability of computational approaches relying on SCF solutions.
• The algorithm's ability to preserve spin symmetry is a key feature for accurate electronic structure calculations.