Abstract:
Most of modern simulation techniques are based on the assumption that the motion of nuclei is well described by classical trajectories while the electrons are treated quantum mechanically. However, some of the most fascinating phenomena in physics and chemistry, such as the process of vision, the dynamics of excitons in photovoltaic systems or the Nobel-prize-winning femto-chemistry experiments of Ahmed Zewail, occur in the so-called non-adiabatic regime where the coupled motion of electrons and nuclei beyond the dynamics on a single Born-Oppenheimer (BO) surface is essentional. To tackle this problem, we start from the exact factorization [1] of the full electron-nuclear wave function into a purely nuclear part and a many-electron wave function which parametrically depends on the nuclear configuration and which has the meaning of a conditional probability amplitude. The equations of motion of these two wave functions provide an ideal starting point to develop efficient algorithms for the study non-adiabatic phenomena. The successful prediction of ultrafast laser-induced isomerization processes [2], the description of decoherence within mixed quantum-classical algorithms [3], calculations of the molecular Berry phase beyond the BO approximation [4] and accurate predictions of vibrational spectroscopy [5], especially dichroism, will demonstrate the power of this novel approach.
[1] A. Abedi, N.T. Maitra, E.K.U. Gross, PRL 105, 123002 (2010).
[2] F. Agostini, S.K. Min, I. Tavernelli, E.K.U. Gross, J Phys Chem Lett 8, 3048 (2017).
[3] S.K. Min, F. Agostini, E.K.U. Gross, PRL 115, 073001 (2015).
[4] S.K. Min, A. Abedi, K.S. Kim, E.K.U. Gross, PRL 113, 263004 (2014).
[5] A. Scherrer, F. Agostini, D. Sebastiani, E.K.U. Gross, R. Vuilleumier, PRX 7, 031035, (2017).
Most of modern simulation techniques are based on the assumption that the motion of nuclei is well described by classical trajectories while the electrons are treated quantum mechanically. However, some of the most fascinating phenomena in physics and chemistry, such as the process of vision, the dynamics of excitons in photovoltaic systems or the Nobel-prize-winning femto-chemistry experiments of Ahmed Zewail, occur in the so-called non-adiabatic regime where the coupled motion of electrons and nuclei beyond the dynamics on a single Born-Oppenheimer (BO) surface is essentional. To tackle this problem, we start from the exact factorization [1] of the full electron-nuclear wave function into a purely nuclear part and a many-electron wave function which parametrically depends on the nuclear configuration and which has the meaning of a conditional probability amplitude. The equations of motion of these two wave functions provide an ideal starting point to develop efficient algorithms for the study non-adiabatic phenomena. The successful prediction of ultrafast laser-induced isomerization processes [2], the description of decoherence within mixed quantum-classical algorithms [3], calculations of the molecular Berry phase beyond the BO approximation [4] and accurate predictions of vibrational spectroscopy [5], especially dichroism, will demonstrate the power of this novel approach.
[1] A. Abedi, N.T. Maitra, E.K.U. Gross, PRL 105, 123002 (2010).
[2] F. Agostini, S.K. Min, I. Tavernelli, E.K.U. Gross, J Phys Chem Lett 8, 3048 (2017).
[3] S.K. Min, F. Agostini, E.K.U. Gross, PRL 115, 073001 (2015).
[4] S.K. Min, A. Abedi, K.S. Kim, E.K.U. Gross, PRL 113, 263004 (2014).
[5] A. Scherrer, F. Agostini, D. Sebastiani, E.K.U. Gross, R. Vuilleumier, PRX 7, 031035, (2017).
