Quantum–Classical Mechanics and the Franck–Condon Principle
Quantum–classical mechanics and the Franck–Condon principle related to quantum mechanics are discussed as two alternative theoretical approaches to molecular optical spectroscopy. The statement of the problem is connected with the singularity of quantum mechanics in describing the joint motion of el...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-04-01
|
| Series: | Computer Sciences & Mathematics Forum |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2813-0324/7/1/55 |
| _version_ | 1797381459832471552 |
|---|---|
| author | Vladimir V. Egorov |
| author_facet | Vladimir V. Egorov |
| author_sort | Vladimir V. Egorov |
| collection | DOAJ |
| description | Quantum–classical mechanics and the Franck–Condon principle related to quantum mechanics are discussed as two alternative theoretical approaches to molecular optical spectroscopy. The statement of the problem is connected with the singularity of quantum mechanics in describing the joint motion of electrons and nuclei in the transient state of “quantum” transitions. This singularity can be eliminated by introducing chaos into the transient state. Quantum mechanics itself, supplemented by chaos (dozy chaos), is called quantum–classical mechanics. Using the simplest example of quantum transitions, it is shown that the results of quantum–classical mechanics in the case of strong dozy chaos correspond to the physical picture based on quantum mechanics and the Franck–Condon principle. The same chaos can be strong for small molecules in standard molecular spectroscopy and simultaneously weak in the photochemistry and nanophotonics of large molecules, where quantum mechanics no longer works. To describe the chaotic dynamics of the transient state, it is necessary to apply quantum–classical mechanics. Thus, the erroneous Franck–Condon physical picture of molecular “quantum” transitions is workable from a practical point of view as long as we are dealing with sufficiently small molecules, just as the erroneous geocentric picture of the world was workable until we went out into outer space. |
| first_indexed | 2024-03-08T20:51:50Z |
| format | Article |
| id | doaj.art-81e31110d9d44618bfc77127eb2f65cc |
| institution | Directory Open Access Journal |
| issn | 2813-0324 |
| language | English |
| last_indexed | 2024-03-08T20:51:50Z |
| publishDate | 2023-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Computer Sciences & Mathematics Forum |
| spelling | doaj.art-81e31110d9d44618bfc77127eb2f65cc2023-12-22T14:02:12ZengMDPI AGComputer Sciences & Mathematics Forum2813-03242023-04-01715510.3390/IOCMA2023-14396Quantum–Classical Mechanics and the Franck–Condon PrincipleVladimir V. Egorov0Photochemistry Center, FSRC “Crystallography and Photonics”, Russian Academy of Sciences, 7a Novatorov Street, 119421 Moscow, RussiaQuantum–classical mechanics and the Franck–Condon principle related to quantum mechanics are discussed as two alternative theoretical approaches to molecular optical spectroscopy. The statement of the problem is connected with the singularity of quantum mechanics in describing the joint motion of electrons and nuclei in the transient state of “quantum” transitions. This singularity can be eliminated by introducing chaos into the transient state. Quantum mechanics itself, supplemented by chaos (dozy chaos), is called quantum–classical mechanics. Using the simplest example of quantum transitions, it is shown that the results of quantum–classical mechanics in the case of strong dozy chaos correspond to the physical picture based on quantum mechanics and the Franck–Condon principle. The same chaos can be strong for small molecules in standard molecular spectroscopy and simultaneously weak in the photochemistry and nanophotonics of large molecules, where quantum mechanics no longer works. To describe the chaotic dynamics of the transient state, it is necessary to apply quantum–classical mechanics. Thus, the erroneous Franck–Condon physical picture of molecular “quantum” transitions is workable from a practical point of view as long as we are dealing with sufficiently small molecules, just as the erroneous geocentric picture of the world was workable until we went out into outer space.https://www.mdpi.com/2813-0324/7/1/55transient state dynamicsdozy chaosquantum–classical mechanicsFranck–Condon principleEgorov nano-resonance |
| spellingShingle | Vladimir V. Egorov Quantum–Classical Mechanics and the Franck–Condon Principle Computer Sciences & Mathematics Forum transient state dynamics dozy chaos quantum–classical mechanics Franck–Condon principle Egorov nano-resonance |
| title | Quantum–Classical Mechanics and the Franck–Condon Principle |
| title_full | Quantum–Classical Mechanics and the Franck–Condon Principle |
| title_fullStr | Quantum–Classical Mechanics and the Franck–Condon Principle |
| title_full_unstemmed | Quantum–Classical Mechanics and the Franck–Condon Principle |
| title_short | Quantum–Classical Mechanics and the Franck–Condon Principle |
| title_sort | quantum classical mechanics and the franck condon principle |
| topic | transient state dynamics dozy chaos quantum–classical mechanics Franck–Condon principle Egorov nano-resonance |
| url | https://www.mdpi.com/2813-0324/7/1/55 |
| work_keys_str_mv | AT vladimirvegorov quantumclassicalmechanicsandthefranckcondonprinciple |