# The Atmospheric Chemistry of Fluoroacetonitrile and the Characterization of the Major Product, Cyanoformyl Fluoride

## TL;DR

This study examines the atmospheric chemistry of fluoroacetonitrile, a potential industrial substitute, and identifies its reaction products and climate impact.

## Contribution

The paper provides new experimental and computational data on the atmospheric reactivity and global warming potential of fluoroacetonitrile.

## Key findings

- The atmospheric lifetime of CH2FCN is 0.45 years with a 100-year global warming potential of 20.
- FCOCN is the only organic product from the Cl-atom reaction, indicating H-abstraction is dominant.
- Quantum calculations show OH radical attack favors abstraction due to lower energy barriers and tunneling.

## Abstract

Fluorinated nitriles have been proposed as low-global-warming-potential substitutes for industrial applications such as plasma etching and as dielectric materials in high-voltage equipment. FT-IR spectroscopy was used to measure the radiative efficiency of CH2FCN and its reactivity towards Cl and OH radicals, and to determine products from the Cl reaction. Relative rate experiments yielded rate constants for Cl and OH reactions of (2.1 ± 0.3) × 10−14 and (7.0 ± 1.0) × 10−14 cm3 molecule−1 s−1, respectively. The estimated atmospheric lifetime of CH2FCN with respect to radical attack was estimated to be 0.45 years, which, combined with the radiative efficiency of 0.042 W m−2 ppb−1, implies a 100-year global warming potential of 20. FCOCN was observed as the only organic product of the Cl-atom reaction in air, consistent with a dominant role for H-abstraction. Absolute infrared cross-sections for FCOCN were determined, to assist future experiments where this molecule may be formed. Quantum calculations at the CBS-APNO//B2PLYP-D3/cc-pVTZ level indicate similar energy barriers to addition and abstraction for OH radical attack, but the looser transition state and greater opportunity for tunneling also favor abstraction in this case.