Accelerating calculations of ultrafast time-resolved electronic spectra with efficient quantum dynamics methods.

Area of Science:

• Quantum dynamics
• Spectroscopy
• Computational chemistry

Background:

• Accurate calculation of quantum time correlation functions is crucial for interpreting time-resolved electronic spectra.
• Current computational methods can be prohibitively expensive, limiting their application.

Purpose of the Study:

• To develop and evaluate three distinct strategies for accelerating the computation of quantum time correlation functions.
• To enhance the efficiency of quantum dynamics simulations for spectroscopic applications.

Main Methods:

• Identifying a minimal set of accurate electronic surfaces.
• Employing diverse split-step algorithms to increase the time step in exact quantum simulations of the time-dependent Schrödinger equation.
• Reducing the number of trajectories required for convergence in approximate semiclassical dynamics.

Main Results:

• Demonstrated efficiency gains in calculating quantum time correlation functions.
• Validated the accuracy of the proposed methods for spectroscopic applications.
• Showcased the applicability of these accelerated methods to complex quantum systems.

Conclusions:

• The presented approaches offer significant speedups for quantum time correlation function calculations.
• These methods provide a more computationally feasible route to analyzing time-resolved electronic spectra.
• The findings pave the way for broader application of quantum dynamics simulations in spectroscopy.