Extracting Inelastic Scattering Cross Sections for Finite and Aperiodic Materials from Electronic Dynamics...

Area of Science:

• Condensed matter physics
• Quantum chemistry
• Materials science

Background:

• Time-dependent electronic structure theory is crucial for studying molecular and condensed-phase systems.
• Existing methods are routinely used for optical absorptivity but less so for scattering phenomena.

Purpose of the Study:

• To demonstrate the utility of electronic dynamics simulations for studying scattering-induced electronic excitations.
• To introduce a novel method for evaluating the electronic dynamic structure factor.
• To investigate morphology-dependent effects in inelastic scattering cross sections.

Main Methods:

• Employing explicit time-dependent electronic structure theory.
• Applying a momentum boost-type perturbation to simulate scattering.
• Transforming reciprocal space density fluctuations into the frequency domain.
• Comparing results with linear response theory transition matrix elements.

Main Results:

• Validated a new method for calculating the dynamic structure factor using electronic dynamics simulations.
• Achieved good agreement between simulation results and linear response theory predictions.
• Applied the method to quasi-one-dimensional systems and graphene nanostructures.
• Captured morphology-dependent effects in inelastic scattering cross sections.

Conclusions:

• Electronic dynamics simulations are a viable tool for analyzing scattering-induced electronic excitations.
• The presented method provides a robust way to evaluate the dynamic structure factor.
• The approach is effective for nanostructured and noncrystalline materials, including graphene derivatives.