Interatomic Coulombic electron capture beyond the virtual photon approximation

Area of Science:

• Atomic and Molecular Physics
• Quantum Chemistry

Background:

• Interatomic Coulombic electron capture (ICEC) is a process where an electron is captured by one species, with energy transferred to a neighbor.
• Existing analytical formulas for ICEC cross sections are accurate only when the interacting species are far apart.

Purpose of the Study:

• To develop an analytical model for predicting ICEC cross sections applicable to situations where species size is comparable to inter-species distance.
• To improve the accuracy of ICEC cross section predictions beyond the asymptotic approximation.

Main Methods:

• Development of a novel analytical model for ICEC cross sections.
• Validation of the model using ab initio R-matrix calculations for various atomic and molecular systems.

Main Results:

• The new analytical model significantly enhances the accuracy of ICEC cross section predictions.
• The model reduces the error of the asymptotic formula by an average of two orders of magnitude.
• The model utilizes readily available parameters: energies and photoionization cross sections of the involved species.

Conclusions:

• The developed analytical model provides a more accurate and broadly applicable method for calculating ICEC cross sections.
• This work bridges the gap in ICEC modeling for systems where species are not asymptotically separated.
• The model's reliance on intrinsic species properties simplifies its application in diverse research areas.