Real-Time Time-Dependent Electron Dynamics

Documentation on the real-time time-dependent self-consistent field (RT-TDSCF) electron dynamics calculation of molecular properties.

Feature List

Available spectroscopies

  • UV/Vis and/or X-ray electron absorption (EAS)
  • UV/Vis and/or X-ray electronic circular dichroism (ECD)


  • non-relativistic one-component (1c) Hartree-Fock (HF) and Kohn-Sham (KS)
  • relativistic 2c HF/KS with the X2C transformed one-electron Dirac Hamiltonian (1eX2C)
  • relativistic 4c matrix/modified Dirac-Hartree-Fock (mDHF) and Dirac-Kohn-Sham (mDKS)
  • scalable speed of light

DFT non-collinear functionals

  • local (SVWN5)
  • GGA (PBE,BLYP,KT2,BP86,PP86)
  • hybrid (PBE0,B3LYP)

Reference wave function models

  • Kramers restricted determinant for closed-shell singlets

Equation-of-motion solvers

  • Magnus propagator with a self-consistent extrapolation-interpolation scheme

External electric field models

  • analytical representation of the Dirac delta impulse
  • Gaussian-type impulse
  • monochromatic cosine wave with/without a linear envelope

Integral evaluation techniques

  • analytic with an in-built restricted kinetic balanced (RKB) condition for the small-component
  • resolution-of-the-identity for the Coulomb two-electron term (RI-J)
  • one-center approximation for the SSSS-type electron repulsion integrals

Additional features

  • selective perturbation/response
  • molecular orbital analysis of spectroscopic transitions
  • parallel execution on shared-memory parallel architectures (SMPs)

Related Publications

M. Repisky, L. Konecny, M. Kadek, S. Komorovsky, O. L. Malkin, V. G. Malkin, and K. Ruud
Excitation energies from real-time propagation of the four-component Dirac-Kohn-Sham equation
J. Chem. Theory Comput. 11, 980–991 (2015)

M. Kadek, L. Konecny, B. Gao, M. Repisky, and K. Ruud
X-ray absorption resonances near L2,3-edges from real-time propagation of the Dirac–Kohn–Sham density matrix
Phys. Chem. Chem. Phys. 17, 22566–22570 (2015)

L. Konecny, M. Kadek, S. Komorovsky, O. L. Malkina, K. Ruud, and M. Repisky
Acceleration of relativistic electron dynamics by means of X2C transformation: application to the calculation of nonlinear optical properties
J. Chem. Theory Comput. 12, 5823–5833 (2016)

L. Konecny, M. Kadek, S. Komorovsky, K. Ruud, and M. Repisky
Resolution-of-identity accelerated relativistic two- and four-component electron dynamics approach to chiroptical spectroscopies
J. Chem. Phys. 149, 204104 (2018)

Program Reference

M. Repisky, S. Komorovsky, M. Kadek, L. Konecny, U. Ekstrom, E. Malkin,
M. Kaupp, K. Ruud, O. L. Malkina, and V. G. Malkin
ReSpect: Relativistic spectroscopy DFT program package
J. Chem. Phys. 152, 184101 (2020)

Additional contributions from
R. Bast (AutoCMake), R. Di Remigio (PCMSolver), I. Malkin-Ondik (DKH2), and S. Knecht (MPI parallelization)

Latest Posts

Useful Links

Our Contacts

Hylleraas Centre
Department of Chemistry
UiT The Arctic University of Norway
Tromsø, NO-9037 Norway