Ab initio studies of the thermal decomposition pathways of 1-bromo-3,3,3-trifluoropropene

作者：Zhang Meiling^*; Lin Zijing

来源：Journal of Molecular Structure (Theochem), 2009, 899(1-3): 98-110.

DOI：10.1016/j.theochem.2008.12.021

• Ab initio
• Halon replacement
• 1-bromo-3,3,3-trifluoropropene
• Transition state
• Vibrational frequencies
• Dissociation pathway

The complex potential energy surface for the unimolecular isomerization and dissociation of 1-bromo-3,3,3-trifluoropropene (CF3CHCBrH), including 12 CF3CHCBrH isomers, 33 interconversion transition states and 13 major dissociation products, is probed theoretically at the CCSD/aug-cc-pVDZ//B3LYP/6-311++G(d, p) level of theory. The geometries, vibrational frequencies and relative energies for various stationary points are determined. Based on the calculated CCSD/aug-cc-pVDZ potential energy surface, the possible 1-bromo-3,3,3-trifluoropropene unimolecular decomposition mechanism is discussed. Eight distinct decomposition pathways of 1-bromo-3,3,3-trifluoropropene (BTP) are investigated at the CCSD/aug-cc-pVDZ//B3LYP/6-311++G(d, p) theory level. The reaction enthalpies and energy barriers are determined. From the energetics, the most feasible decomposition pathways for 1-bromo-3,3,3-trifluoropropene are those that lead to CF3CCH + HBr and CF2CCBrH + HF. Considering the extreme high flame temperature, the decomposition pathways are competitive. The BTP dissociation occurs via concerted molecular eliminations.

• 出版日期2009-4-15
• 单位天津医科大学; 中国科学技术大学