Grand Séminaire d'Institut

Mardi 16 Janvier 2024 à 11h00.

Introduction to the Multi-Configuration Time-Dependent Hartree (MCTDH) method

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Many molecular processes, ranging from fundamental to applied problems, are known today to be impacted by strong nuclear quantum mechanical effects, including phenomena like tunneling, zero point energy effects, or non-adiabatic transitions. Recent success in helping to understand experimental observations in fields like heterogeneous catalysis, photochemistry, reactive scattering, optical spectroscopy, or femto- and attosecond chemistry and spectroscopy underlines that nuclear quantum mechanical effects affect many areas of chemical and physical research. The correct theory to describe the corresponding dynamics is Molecular Quantum Dynamics [1,2]. In contrast to standard quantum chemistry calculations, where the nuclei are treated classically, molecular quantum dynamics can cover quantum mechanical effects in their motion. New strategies have been developed to extend the studies to systems of increasing size. We give a general presentation of the Multi-Configuration Time-Dependent Hartree method (MCTDH) [3,4,5]. MCTDH can be seen as a time-dependent MCSCF approach for the nuclei where wavepackets are propagated on one or several potential energy surfaces. Several emphasis will be placed on the numerical and algortithmic challenges we have to face in this field of research.

[1] Molecular Quantum Dynamics, From Theory to Applications, Ed. F . Gatti, Springer, (2014) Heidelberg.
[2] Quantum Physics, Applications to Chemistry, F. Gatti, B. Lasorne, H.-D. Meyer and A. Nauts, Lectures Notes in Chemistry, Springer, 2017.
[3] H.-D. Meyer, U. Manthe, and L.S. Cederbaum, The multi-configurational time-dependent Hartree approach. Chem. Phys. Lett. 165 (1990), 73.
[4] M. H. Beck, A. Jäckle, G. A. Worth and H.-D. Meyer, The multiconfiguration time-dependent Hartree method: A highly efficient algorithm for propagating wavepackets, Physics Reports 324 (2000),
[5] H.-D. Meyer, F. Gatti, and G. A. Worth, editors, Multidimensional Quantum Dynamics: MCTDH Theory and Applications., Wiley-VCH,(2009),Weinheim

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