Proton transfer in acetylacetone and its α-halo derivatives. Issue 1 (30th November 2015)

• Record Type: Journal Article
• Authors: Dolati, Fatemeh; Tayyari, Sayyed Faramarz; Vakili, Mohammad; Wang, Yan Alexander
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 1(2016)
• Page Start: 344
• Page End: 350
• Publication Date: 2015-11-30
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c5cp03845f
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : A two-dimensional potential energy function has been applied to study the bent intramolecular H-bonds within acetylacetone and its α-halo derivatives. The theoretically predicted proton transfer barrier heights correlate very well with geometrical parameters and electronic properties related to the H-bond strength. Abstract : A two-dimensional potential energy surface was utilized to treat the proton transfer in acetylacetone (AA) and its α-halo derivatives: α-fluoro-(FAA), α-chloro-(ClAA), and α-bromo-acetylacetone (BrAA). This potential energy function, which couples O–H stretching and in-plane bending vibrations, was acquired through ab initio calculations for a fixed skeleton geometry. The resulting potential energy surfaces were then used to calculate the proton tunneling frequencies and proton transfer barrier heights. The barrier heights (the energy difference between the saddle point and the minima) calculated at the MP2/6-31G(2d, p) level of theory for proton transfers in AA, FAA, ClAA, and BrAA are 7.2, 9.4, 6.3, and 5.9 kcal mol −1, respectively. The theoretically predicted proton transfer barrier heights exhibit excellent linear correlations with geometrical, electronic structural, and topological parameters evaluated by the atoms-in-molecule (AIM) and natural bond orbital (NBO) analyses.