<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings"^^ . "In quantum chemistry, a full quantum dynamical description of large many-body systems\r\nis not currently feasible. One can consider both classical and semi-classical treatments of\r\napproximating the quantum dynamics of molecular systems to simulate simpler dynamics.\r\nMotivated by their cost-effectiveness and the fact that chemical dynamics take place often\r\nin an energy and density-of-states regime where a classical description can be meaningful,\r\na classical description of the quantum dynamics of systems is explored in this dissertation.\r\nWe first illustrate how the reaction rate is affected by the cavity effect. cis-trans iso�merization of HONO is used as an example to demonstrate the cavity-controlled reactivity.\r\nDue to the high dimensionality of the potential energy surface, we describe the reaction\r\nrate through a classical reactive flux method. The quantum Hamiltonian for simulating\r\ncavity-modified molecular dynamics is transformed into a classical mapping Hamiltonian.\r\nWe consider a single molecule inside the cavity. For simplicity, we assume the cavity is\r\ncoupled to an aligned molecule. The x− aligned case is studied in both low-friction and\r\nstrong-friction regimes of the reaction coordinate. The low(strong)-friction regime is also\r\nknown as the underdamped(overdamped) regime, which is mentioned in Grote-Hynes theory. In the underdamped regime, we illustrate the key difference between a single molecule\r\nand a collective of molecules with fixed Rabi splitting. We also show a modification of the\r\nreaction rate with different cavity frequencies for different aligned cases. Our results show\r\nthat the modification of the reaction rate is related to the solvent environment. This will be\r\ndescribed in chapter 3.\r\nWe then consider free-orientated molecules inside the cavity within the underdamped\r\nregime. Compared with aligned cases, the free orientation of molecules leads to a disorder\r\nof light-matter coupling, which should be observed in experimental results. Since a thermally excited molecule passing through the barrier is a rare event, we consider N molecules\r\ninside the cavity with 1 activated molecule and N −1 non-activated molecule. We aim to see\r\nhow the reaction rate is affected by the number of molecules with fixed coupling strength.\r\nWe connect the enhancing rate by increasing the number of molecules with the energy transfer efficiency from the activated molecule to the cavity. And the efficiency is sensitive to\r\nthe resonant frequency. Based on this observation, we also show the modification of the reaction rate by tuning the lifetime of the cavity. Our findings shed important new light on\r\nthe question of collective effects in chemical reactivity under vibrational strong coupling.\r\nThis will be described in chapter 4.\r\nOn the other hand, we turn to describe the fermionic dynamics through Meyer-Miller\r\nmapping. In chapter 5, We proceed by describing the relation between the initial phase\r\nspace density of the classically mapped system and the initial configuration of the electrons,\r\nand propose strategies to sample this phase space density. We compare the MM mapping\r\nwith exact quantum results and with different mappings explicitly designed for fermions,\r\nnamely the SM with and without the inclusion of antisymmetry (the latter corresponds to the\r\noriginal MW mapping), and to the LMM. We then compare Hubbard and impurity Hamiltonians, with and without interactions, and consider as well a model for excitonic energy\r\ntransfer between chromophores. In this model with interactions we show that the classical MM mapping is able to capture interference effects caused by the presence of different\r\nenergy transfer pathways leading to the same final state, both when the interferences are constructive and destructive. Our results show that the construction of the maximal fermionic\r\noccupation does not seem to be necessary. Also, the performance of the mappings is sensitive to sampling strategies of the initial phase-space distribution for fermions"^^ . "2023" . . . . . . . "Jing"^^ . "Sun"^^ . "Jing Sun"^^ . . . . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (PDF)"^^ . . . "PhD_thesis.pdf"^^ . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (Other)"^^ . . . . . . "preview.jpg"^^ . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (Other)"^^ . . . . . . "medium.jpg"^^ . . . "Cavity-controlled thermal reactivity and fermionic dynamics using classical mappings (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #34075 \n\nCavity-controlled thermal reactivity and fermionic dynamics using classical mappings\n\n" . "text/html" . . . "500 Naturwissenschaften und Mathematik"@de . "500 Natural sciences and mathematics"@en . .