MMVBSCD · Semi-classical dynamics on large systems using the MMVB method: Applications to photochemical switches and electron transfer systems
6РП — Действия „Мария Кюри“
- Период
- 2006-02-01 → 2008-01-31
- Финансиране от ЕС
- 160 294 €
- Участници
- 1
- Схема
- IIF
Линиите свързват координатора с партньорите.
Накратко на български
Разработваният метод MMVB анализира поведението на големи молекули при въздействие от светлина, като например при радикалните катиони на пирена и перилена. Това помага за по-доброто разбиране на процесите по пренос на електрони и фотохимичната стабилност на органичните съединения.
Кратко обяснение, генерирано от езиков модел по текста на CORDIS. Оригиналът е по-долу.
Резултати накратко
Final Activity Report Summary - MMVBSCD (Semi-classical dynamics on large systems using the MMVB method: Applications to photochemical switches and electron transfer systems)
The low-energy excitations determine the physical properties and chemical reactivity of a vast number of molecular systems. The spin Hamiltonian valence bond approach allows for an efficient treatment of large active spaces. When combined with molecular mechanics the resulting hybrid method (molecular mechanics - valence bond, MMVB) becomes a unique tool for studying photochemistry of large molecules. The method was originally developed only for the limiting case of covalent states and active spaces with equal numbers of electrons and orbitals. The main result of the fellowship is the extension of the MMVB method to the general active spaces without any restrictions on the numbers of electrons and orbitals. Also, the new method allows considering the charge-transfer excited states. Both developments significantly extend the applicability of the method. The resulting magnetic Hamiltonians have been partially parameterised and all the algorithms have been implemented allowing for a detailed analysis of potential energy surfaces. The practical applications explaining the photostability and relaxation mechanism of pyrene radical cation and fluorescence of perylene radical cation as well as properties of other polycyclic aromatic hydrocarbon cations demonstrate the high potential of the extended MMVB method in theoretical studies of photochemical behaviour.
Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз
Цел на проекта
The aim of this proposal is the study of the complex long-time dynamics of molecular switches and electron transfer systems. It will be achieved by the development of a hybrid approach allowing for highly accurate simulations on large chemical, biological and physical systems due to combination of quantum description for reactive center and classical force fields for surrounding molecular framework. The hybrid MM-VB (Molecular Mechanics ¿ Valence Bond) method which is proven to be a useful tool for studyin g non-adiabatic dynamics will be extended to solve a series of frontier problems in modern chemistry. The photochemistry of azobenzene and fulgides will be thoroughly studied because they are the prominent members of the family of photochemical molecular s witches and have a great potential in development of optoelectronic and photooptical devices. It will require generating reliable parameters for nitrogen and oxygen and calibration of the hybrid MM-VB force field. The second extension is based on the gener alization of the VB treatment of the quantum region. It will allow the MM-VB method to treat dynamics of charged species (for example, radical-cations). It will open access to dynamical studies of electron transfer in biological systems (for example, photo synthetic reaction) as well as to thorough analysis of conducting polymers. The project is based on the experience of the host and the applicant in theoretical methods for large molecules. It will result in new fundamental knowledge about photochemistry of molecular switches and electron transfer systems as well as in computer software for large-scale molecular simulations. The project will lead to the mutual benefit because the joint research will allow strengthening the methodological grounds of the hybri d quantum/classical dynamical simulations and it will also result in novel applications in one of the most innovative areas of chemistry and material science.""
Оригинален текст от CORDIS (на английски).
Участници
- IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY AND MEDICINE · LONDONКоординаторОбединеното кралство
Връзки
Данни: CORDIS, © Европейски съюз