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Non-empirical Anharmonic Vibrational Perturbation Theory Applied to Biomolecules: Free-Base Porphinстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 28 апреля 2015 г.
- Авторы: Krasnoshchekov Sergey V., Stepanov Nikolai F.
- Журнал: The Journal of Physical Chemistry A: Molecules, Clusters, and Aerosols
- Том: 119
- Номер: 9
- Год издания: 2015
- Издательство: American Chemical Society
- Местоположение издательства: United States
- Первая страница: 1616
- Последняя страница: 1627
- DOI: 10.1021/jp5077092
- Аннотация: Anharmonic vibration frequencies and intensities (infrared and Raman) of an isolated free-base porphin molecule are predicted from the quantum-mechanical (QM) geometry, the “semi-diagonal” quartic force field, and dipole moment and polarizability surfaces. The second-order vibrational perturbation theory plus the numerical diagonalization of the Hamiltonian matrix containing off-diagonal Fermi and Darling-Dennison resonance couplings (VPT2+WK) is used. The QM calculations were carried out with the Becke-Lee-Yang-Parr composite exchange-correlation functional (B3LYP) and with the 6-31+G(d,p) basis set. The harmonic force field for the equilibrium configuration was transformed into nonredundant local symmetry internal coordinates, and normal coordinates were defined. The “semi-diagonal” quartic rectilinear normal coordinate potential energy surface (PES), as well as the cubic surfaces of dipole moment (p) and polarizability (α) components, needed for the VPT2+WK calculation, were constructed by a five-point finite differentiation of Hessians (for PES) and of the values and first derivatives of p and α. They were obtained at the point of equilibrium and for 432 displaced configurations. This theoretical approach provides very good agreement between the predicted and experimental frequencies and intensities. However, the favorable result can be partly attributed to error cancellation within the B3LYP/6-31+G(d,p) QM model, as observed in earlier studies. Reassignments of some observed bands are proposed.
- Добавил в систему: Краснощеков Сергей Вадимович
Прикрепленные файлы
| № | Имя | Описание | Имя файла | Размер | Добавлен |
|---|---|---|---|---|---|
| 1. | Полный текст | 2015_J._Phys._Chem._A_1199_pp.1616-1627_MY_424345707172_Kra… | 681,8 КБ | 22 апреля 2015 [Sergey.Krasnoshchekov] | |
| 2. | jp5077092_si_001.pdf | jp5077092_si_001.pdf | 726,0 КБ | 14 ноября 2014 [Sergey.Krasnoshchekov] |