Mutual Information in Conjugate Spaces for Neutral Atoms and Ions

Area of Science:

• Quantum Chemistry
• Atomic Physics
• Computational Chemistry

Background:

• Accurate electron density descriptions are crucial for understanding atomic and ionic properties.
• Electron correlation, the interaction between electrons, significantly influences atomic behavior.
• Existing methods may not fully capture the nuances of electron correlation in diverse systems.

Purpose of the Study:

• To quantify the discrepancy between one-electron and two-electron densities in atoms and ions.
• To interpret these discrepancies as a measure of electron correlation.
• To investigate the influence of electron shell structure on interelectronic correlation.

Main Methods:

• Utilizing mutual information (I) and the Quantum Similarity Index (QSI).
• Analyzing electron densities in both position and momentum conjugate spaces.
• Comparing double-variable electron pair densities with products of one-particle densities.

Main Results:

• Quantified electron correlation for neutral atoms (Z=N) and singly charged ions (|N-Z|=1) up to Z=103 and N=54.
• Demonstrated that discrepancies in electron densities serve as a measure of electron correlation.
• Revealed the significant impact of electron shell structure on interelectronic correlation across the Periodic Table.

Conclusions:

• Electron correlation can be effectively quantified by analyzing discrepancies in electron densities.
• The shell structure of atoms and ions plays a pivotal role in determining interelectronic correlation.
• This approach provides a robust framework for studying electron correlation in a wide range of atomic systems.