2016/11/14 by Loïc Joubert-Doriol, Joubert-Doriol, Loic, Janakan Sivasubramanium +5
Physics and Astronomy · #Advanced Chemical Physics Studies #Chemical Physics (physics.chem-ph) #Computational Physics (physics.comp-ph) #FOS: Physical sciences #Quantum Physics (quant-ph) #Quantum, superfluid, helium dynamics #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.1611.04442
openalex publication_date 2016/11/14 · openalex created_date 2022/10/02 · openalex updated_date 2026/07/28
On-the-fly quantum nonadiabatic dynamics for large systems greatly benefits\nfrom the adiabatic representation readily available from the electronic\nstructure programs. However, frequently occurring in this representation\nconical intersections introduce non-trivial geometric or Berry phases which\nrequire a special treatment for adequate modelling of the nuclear dynamics. We\nanalyze two approaches for nonadiabatic dynamics using the time-dependent\nvariational principle and the adiabatic representation. The first approach\nemploys adiabatic electronic functions with global parametric dependence on the\nnuclear coordinates. The second approach uses adiabatic electronic functions\nobtained only at the centres of moving localized nuclear basis functions (e.g.\nfrozen-width Gaussians). Unless a gauge transformation is used to enforce\nsingle-valued boundary conditions, the first approach fails to capture the\ngeometric phase. In contrast, the second approach accounts for the geometric\nphase naturally because of the absence of the global nuclear coordinate\ndependence in the electronic functions.\n