A theoretical investigation on the mechanistic and kinetic study of 2,2,3,3,4,4,5,5-octafluorocyclopentanol with OH radicals and Cl atoms and its implications in new particle formation

Abstract

Fluorinated alcohols are used in various industrial applications, including coatings, paints, adhesives, polymers, waxes, and polishes, as well as for cleaning electronic components. Consequently, the presence of fluorine atoms in these compounds contributes to their atmospheric persistence, allowing them to act as potent greenhouse gases, even at trace concentrations. The potential risks and hazards of novel chemical substances were assessed before they were introduced into society. Therefore, a key component of atmospheric chemistry in our study is the oxidation of 2,2,3,3,4,4,5,5-octafluorocyclopentanol (cyc-(CF₂)₄CHOH–) by hydroxyl (OH) radicals and chlorine (Cl) atoms, as well as how this molecule participates in new particle formation (NPF) in the atmosphere, studied through molecular dynamics (MD) simulations. All reaction energetics and thermodynamic parameters were calculated utilizing the M06-2X/6-311+G(2d,2p) and MP2/6-311+G(2d,2p) methodologies. The resulting optimized geometries were then employed for single-point energy calculations at the CCSD(T) level using cc-pVXZ (D and T) basis sets. Complete basis set (CBS) extrapolation was performed to obtain accurate rate coefficient calculations. Four hydrogen atom abstraction channels are feasible for the aforementioned title reactions. Possible H-abstraction reaction pathways were identified for these atmospheric oxidising agents, and the rate coefficients were evaluated over the 220–420 K temperature range. The atmospheric implications of the cyc-(CF₂)₄CHOH– compound were computed based on its rate coefficient values, and its atmospheric fate and implications are discussed.