A new molecular mechanics MM3 force field has been developed based on various experimental data as well as ab initio calculations. Computergenerated molecular structures and energy values were compared with experimentally determined data. The acyl halides studied were formyl halides, acetyl halides,
Quantum-mechanical and molecular mechanics conformational analysis of 1,5-cyclooctadiene
โ Scribed by Rocha, Willian R.; De Almeida, Wagner B.
- Publisher
- John Wiley and Sons
- Year
- 1997
- Tongue
- English
- Weight
- 248 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0192-8651
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โฆ Synopsis
The 1,5-cyclooctadiene COD molecule can easily form complexes with transition metals with the molecular structure of various of these complexes being proposed with the aid of X-ray diffraction methods. The fact that the complexes exhibit weak metalแCOD bonds makes it very important in inorganic synthesis and ลฝ . catalysis. In this work the potential energy surface PES for the COD molecule ลฝ was comprehensively investigated: first with molecular mechanics using the . MM3 force field ; and, in a second stage, at the ab initio HartreeแFock level of theory employing the 3แ21G U , 6แ31G, and 6แ31G U basis sets and also including electron correlation effects at the MollerแPlesset second-order perturbation theory level. This work revealed that there are three distinct conformers of the COD molecule with the predicted lowest energy conformation being in agreement with the proposed structure based on experimental electron diffraction data.
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