Molecular structures and vibrational spectra of 2-, 3-and 4-ethylpyridines and 2-, 3-and 4-vinylpyridines by density functional theory and ab initio Hartree–Fock calculations

Autor:	Mustafa Böyükata, Yusuf Sert, Fatih Ucun
Rok vydání:	2012
Předmět:	Bond length Materials science Molecular geometry Physics::Atomic and Molecular Clusters Ab initio Hartree–Fock method General Physics and Astronomy Density functional theory Physics::Chemical Physics Atomic physics Electronic band structure HOMO/LUMO Basis set
Zdroj:	Indian Journal of Physics. 86:859-869
ISSN:	0974-9845 0973-1458
DOI:	10.1007/s12648-012-0141-z
Popis:	The molecular structures, vibrational frequencies and corresponding vibrational assignments of 2-, 3- and 4-ethyl and vinyl pyridines have been calculated by ab initio Hatree-Fock (HF) and density functional theory (B3LYP) methods with 6-311++G(d,p) basis set level. The vibrations for the vinylpyridines were adapted to their C-s symmetries. The calculated frequencies and optimized geometric parameters (bond lengths and bond angles) were seen to be in a well agreement with the experimental data. The comparison of the observed and calculated results also showed that the scaled B3LYP is superior to the scaled HF method for both the vibrational frequencies and the geometric parameters. Infrared intensities and Raman activities have also been reported. In addition, the highest occupied molecular orbital and lowest unoccupied molecular orbital energies of all the compounds have been simulated, and their energy band gaps have been determined.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b3712885cb60b67ae5cb54cf4554c9cf https://doi.org/10.1007/s12648-012-0141-z Zobrazit plný text záznamu Full text from SpringerLink