The maximum occupancy condition for the localized property-optimized orbitals.

Area of Science:

• Quantum Chemistry
• Computational Chemistry
• Theoretical Chemistry

Background:

• Localized orbitals are crucial for understanding chemical bonding and molecular properties.
• Existing methods for generating localized orbitals include Natural Bond Orbitals (NBOs).
• Chemist's Localized Property-optimized Orbitals (CLPOs) offer a new approach based on optimal property partitioning.

Purpose of the Study:

• To analytically demonstrate that CLPOs form Lewis structures with maximal electron occupancy.
• To establish the relationship between CLPOs and NBOs under specific conditions.
• To compare the performance of CLPO and NBO methods.

Main Methods:

• Analytical derivation of CLPO properties.
• Ab initio calculations using the JANPA program.
• Comparison of CLPO and NBO performance on a dataset of 7101 small molecules.

Main Results:

• CLPOs achieve nearly maximum total electron occupancy, forming optimal Lewis structures.
• Under single-determinant wavefunctions with minimal delocalization, CLPOs optimize similar quantities to NBOs.
• The study establishes a theoretical link between CLPOs and NBOs.

Conclusions:

• CLPOs provide a robust method for generating localized orbitals that closely resemble Lewis structures.
• The findings bridge the gap between CLPO and NBO methodologies.
• The comparative analysis validates the utility of both CLPO and NBO approaches in computational chemistry.