Rate coefficients of hydroxyl radical reaction with dimethyl ether over a temperature range of 257–333 K

Highlights: • Rate constant of OH radical reaction with dimethyl ether in 257–333 K temperature range. • Tropospheric lifetime of dimethyl ether. • Radiative forcing and global warming potential for dimethyl ether. The reaction of dimethyl ether (DME) with OH radical was studied using a laser photolysis-laser induced fluorescence technique in the temperature range of 257–333 K at 30 Torr. The temperature dependent rate coefficient is represented by the expression, $k\left(T\right)=\left(9.7\pm 1.0\right)\times {10}^{-12}\exp \left(-\left(380\pm 25\right)/T\right){cm}^3{molecules}^{-1}{s}^{-1}$ and atmospheric lifetime was found to be 4.7 days. To elucidate the reaction mechanism and complement the experimental work, the energies and structures of the reactants and transition states involved were determined theoretically using the G3 method. The radiative forcing and the global warming potential for 100 years time horizon of DME were estimated to be 0.03 W m⁻² ppb⁻¹ and 0.02, respectively.