Partial widths of shape resonances in pyridine and uracil using the stabilization method.

Area of Science:

• Computational Chemistry
• Theoretical Chemistry
• Chemical Physics

Background:

• Low-energy electron attachment to molecules forms shape resonances, vital for electron-driven chemical reactions.
• Understanding partial decay widths offers deeper insights into resonance auto-detachment dynamics.

Purpose of the Study:

• To investigate the utility of bound state methods, specifically the stabilization method, for determining partial widths in medium-sized organic molecules.
• To analyze the contributions of various angular momentum functions (s, p, d, f, g, h, i) to shape resonance widths.

Main Methods:

• Employed the analytic-continuation based stabilization method coupled with the equation-of-motion electron attachment coupled cluster method.
• Utilized a center-of-mass based placement of diffuse functions to obtain angular momentum-resolved partial widths.
• Applied the technique to pyridine and uracil.

Main Results:

• The dominant angular momentum component of resonance widths strongly correlates with the nodal structure of the resonant orbital.
• Higher angular momentum functions (d, f, g, h) are crucial for accurate resonance width calculations.
• The center-of-mass approach mitigates uncertainties associated with atom-centered schemes in the stabilization method.

Conclusions:

• The center-of-mass based stabilization method is effective for calculating partial widths of shape resonances in organic molecules.
• This approach provides a more robust understanding of electron-molecule interactions and decay dynamics.
• Accurate characterization of shape resonances is essential for predicting electron-driven chemical processes.