Vibrational spectrum, ab initio calculations, conformational stabilities and assignment of fundamentals of the Ci conformer of 1,4-dichlorobutane
| Autor: | Howard D. Stidham, Arthur J. LaPlante |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Models
Molecular Spectrophotometry Infrared Infrared Ab initio Analytical chemistry Molecular Conformation Spectrum Analysis Raman Molecular physics Vibration Analytical Chemistry chemistry.chemical_compound symbols.namesake Ab initio quantum chemistry methods Dichlorobutane Computer Simulation Instrumentation Conformational isomerism Spectroscopy Electronic correlation Chemistry Hydrocarbons Halogenated Temperature Atomic and Molecular Physics and Optics Dipole symbols Raman spectroscopy |
| Zdroj: | Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy. 71(2) |
| ISSN: | 1386-1425 |
| Popis: | The infrared and Raman spectrum of 1,4-dichlorobutane is reported in solid, liquid and gas. Ab initio calculations for the nine stable or metastable conformers of 1,4-dichlorobutane are reported for Moller-Ploessett second order electron correlation and B3LYP density functionals with a variety of basis sets, using approximations as high as 6-311+g(2d, 2p). Normal coordinate calculations were conducted for the nine conformers and the results used to provide assignments for some of the observed infrared and Raman bands. An attempt to use the assignments together with the ab initio intensities or Raman activities to investigate the composition of the liquid at room temperature proved modestly successful, and suggested that the populations are altered from those expected in the gas phase by interactions of the permanent electric dipole moments with the dipolar plasma in which the conformers are immersed in the liquid. A substantial disagreement between the Moeller-Ploessett and density functional results is reported, and the calculation of intensities and activities is insufficiently accurate to allow detailed interpretation of the spectrum of the room temperature liquid. A complete assignment of fundamentals is given for the conformer of Ci symmetry, and one Raman and one infrared band is identified with the C2h conformer. All the other infrared and Raman bands in the liquid or the gas are composites of several contributors. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect