The Hylleraas Centre would like to congratulate this years Nobel laureates in physics. The fact that one experimentally now can follow the motion of electrons in real time holds great promise for our understanding of the fundamental building blocks of atoms and molecules.
Computational chemistry can aid in this understanding and help interpret experimental observations. In order to do so, we have to solve the time-dependent Schrödinger or Dirac equations by exposing the electron density to an electromagnetic wave or pulse, and propagating the electron density in time.
The first real-time simulations of changes in the electron density when exposed to electromagnetic fields appeared already in the Centre for Theoretical and Computational Chemistry in 2012, where real-time calculations where used to study plasmon resonances [1,2].
We then extended the real-time methods as a tool to study molecular properties at the relativistic density functional level of theory [3-6], before turning to the real-time propagation of accurate wave functions models such as the coupled-cluster approximations [7-13].
In more recent years, we have studied electron dynamics both in strong magnetic fields [14,15], beyond the so-called Born-Oppenheimer approximation [16], and more directly addressing attosecond spectroscopic processes [17,18].
This years Nobel Laureates in physics have been a great inspiration to many us at here at the Hylleraas centre, and we are happy that we have been able to contribute in our own, theoretical way, to this exciting field.
Literature
[1] B. Gao, K. Ruud and Y. Luo, "Plasmon resonances in linear noble-metal chains". J. Chem. Phys. 137, 194307 (2012)
[2] B. Gao, K. Ruud and Y. Luo, "Shape-Dependent Electronic Excitations in Metallic Chains". J. Phys. Chem. C, 118, 13059 (2014).
[3] M. Repisky, L. Konecny, M. Kadek, S. Komorovsky, V. G. Malkin, O.L. Malkina and K. Ruud, "Real-time propagation of relativistic time-dependent Dirac--Kohn--Sham equation: application to excitation energies". J. Chem. Theory Comp. 11, 980 (2015)
[4] M. Kadek, M. Repisky, L. Konecny, B. Gao and K. Ruud, "X-ray Absorption Resonances near L2,3-edges from Real-Time Propagation of the Dirac--Kohn--Sham equation". Phys. Chem. Chem. Phys. 17, 22566 (2015).
[5] L. Konecny, M. Kadek, S. Komorovsky, O. L. Malina, K. Ruud and M. Repisky, "Acceleration of relativistic electron dynamics by means of X2C transformation: application to the calculation of non-linear optical properties". J. Chem. Theory Comp. 12, 5823 (2016).
[6] 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).
[7] T. B. Pedersen and S. Kvaal, "Symplectic integration and physical interpretation of time-dependent coupled-cluster theory". J. Chem. Phys. 150, 144106 (2019).
[8] H. E. Kristiansen, Ø. S. Schøyen, S. Kvaal and T. B. Pedersen, "Numerical stability of time-dependent coupled-cluster methods for many-electron dynamics in intense laser pulses". J. Chem. Phys. 152, 071102 (2020).
[9] H. E. Kristiansen, B. S. Ofstad, E. Hauge, E. Aurbakken, Ø. S. Schøyen, S. Kvaal and T. B. Pedersen, "Linear and Nonlinear Optical Properties from TDOMP2 Theory". J. Chem. Theory Comp. 18, 3687 (2022).
[10] B. S. Ofstad, H. E. Kristiansen, E. Aurbakken, Ø. S. Schøyen, S. Kvaal and T. B. Pedersen, "Adiabatic extraction of nonlinear optical properties from real-time time-dependent electronic-structure theory". J. Chem. Phys. 158, 154102 (2023)
[11] T. B. Pedersen, H. E. Kristiansen, T. Bodenstein, S. Kvaal and Ø. S. Schøyen, "Interpretation of Coupled-Cluster Many-Electron Dynamics in Terms of Stationary States". J. Chem. Theory Comp. 17, 388 (2021).
[12] B. S. Ofstad, E. Aurbakken, Ø. S. Schøyen, H. E. Kristiansen, S. Kvaal and T. B. Pedersen, "Time-dependent coupled-cluster theory". Wiley Interdisciplinary Reviews Computational Molecular Science 13, e1666 (2023).
[13] E. Hauge, H. E. Kristiansen, L. Konecny, M. Kadek, M. Repisky and T. B. Pedersen, "Cost-Efficient High-Resolution Linear Absorption Spectra Through Extrapolating the Dipole Moment from Real-Time Time-Dependent Electronic-Structure Theory". J. Chem. Theory Comput., accepted for publication (2023).
[14] M. Wibowo, T. J. P. Irons and A. M. Teale, "Modeling Ultrafast Electron Dynamics in Strong Magnetic Fields Using Real-Time Time-Dependent Electronic Structure Methods." J. Chem. Theory Comp. 17, 2137 (2021).
[15] B. S. Ofstad, M. Wibowo-Teale, H. E. Kristiansen, E. Aurbakken, M. P. Kitsaras, Ø. S. Schøyen, E. Hauge, T. J. P. Irons, S. Kvaal, S. Stopkowicz, A. M. Wibowo-Teale and T. B. Pedersen, "Magnetic optical rotation from real-time simulations in finite magnetic fields". arXiv:2308.06003 (2023).
[16] L. Adamowicz, S. Kvaal, C. Lasser and T. B. Pedersen, "Laser-induced dynamic alignment of the HD molecule without the Born-Oppenheimer approximation". J. Chem. Phys. 157, 144302 (2022).
[17] T. Moitra, L. Konecny, M. Kadek, A. Rubio, M. Repisky, "Accurate Relativistic Real-Time Time-Dependent Density Functional Theory for Valence and Core Attosecond Transient Absorption Spectroscopy". J. Phys. Chem. Lett. 14, 1714 (2023).
[18] E. Aurbakken, B. S. Ofstad, H. E. Kristiansen, Ø. S. Schøyen, S. Kvaal, L. K. Sørensen, R. Lindh and T. B. Pedersen, "Transient spectroscopy from time-dependent electronic-structure theory without multipole expansions". Phys. Rev. A, accepted for publication (2023).