Real-Time TDDFT Using Noncollinear Functionals.

Area of Science:

• Quantum chemistry
• Computational physics
• Materials science

Background:

• Collinear functionals are standard in density functional theory (DFT) and time-dependent DFT (TDDFT).
• Generalizing these to noncollinear forms is crucial for describing complex magnetic phenomena.
• The multicollinear approach offers a pathway to achieve this generalization.

Purpose of the Study:

• To demonstrate the application of the multicollinear approach in real-time TDDFT.
• To simulate electronic absorption spectra, Rabi resonance, and precession in magnetic systems.
• To investigate the role of exchange-correlation torque in spin dynamics.

Main Methods:

• Application of the multicollinear approach within real-time TDDFT.
• Simulation of electronic absorption spectra.
• Modeling of Rabi resonance and magnetic precession in a two-center system.

Main Results:

• Successful simulation of electronic absorption spectra and magnetic phenomena.
• Demonstration of nonvanishing local exchange-correlation torque.
• Insights into the evolution of the magnetization vector.

Conclusions:

• The multicollinear approach is effective for real-time TDDFT simulations.
• The method provides valuable insights into spin dynamics and magnetic torques.
• This work facilitates further exploration of quantum phenomena in magnetic systems.