The favorable routes for the hydrolysis of CH 2 OO with (H 2 O) n ( n = 1–4) investigated by global minimum searching combined with quantum chemical methods

• Published in: Physical chemistry chemical physics : PCCP Vol. 23; no. 22; pp. 12749 - 12760
• Main Authors: Wang, Rui, Wen, Mingjie, Liu, Shuai, Lu, Yousong, Makroni, Lily, Muthiah, Balaganesh, Zhang, Tianlei, Wang, Zhiyin, Wang, Zhuqing
• Format: Journal Article
• Language: English
• Published: 09.06.2021
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/D0CP00028K

The hydrolysis reaction of CH 2 OO with water and water clusters is believed to be a dominant sink for the CH 2 OO intermediate in the atmosphere. However, the favorable route for the hydrolysis of CH 2 OO with water clusters is still unclear. Here global minimum searching using the Tsinghua Global Minimum program has been introduced to find the most stable geometry of the CH 2 OO⋯(H 2 O) n ( n = 1–4) complex firstly. Then, based on these stable complexes, favorable hydrolysis of CH 2 OO with (H 2 O) n ( n = 1–4) has been investigated using the quantum chemical method of CCSD(T)-F12a/cc-pVDZ-F12//B3LYP/6-311+G(2d,2p) and canonical variational transition state theory with small curvature tunneling. The calculated results have revealed that, although the contribution of CH 2 OO + (H 2 O) 2 is the most obvious in the hydrolysis of CH 2 OO with (H 2 O) n ( n = 1–4), the hydrolysis of CH 2 OO with (H 2 O) 3 is not negligible in atmospheric gas-phase chemistry as its rate is close to the rate of the CH 2 OO + H 2 O reaction. The calculated results also show that, in a clean atmosphere, the CH 2 OO + (H 2 O) n ( n = 1–2) reaction competes well with the CH 2 OO + SO 2 reaction at 298 K when the concentrations of (H 2 O) n ( n = 1–2) range from 20% relative humidity (RH) to 100% RH, and SO 2 is 2.46 × 10 11 molecules per cm 3 . Meanwhile, when the RH is higher than 40%, it is a new prediction that the CH 2 OO + (H 2 O) 3 reaction can also compete well with the CH 2 OO + SO 2 reaction at 298 K. Besides, Born–Oppenheimer molecular dynamics simulation results show that all the favorable channels of the CH 2 OO + (H 2 O) n ( n = 1–3) reaction cannot react on a time scale of 100 ps in the NVT simulation. However, the NVE simulation results show that the CH 2 OO + (H 2 O) 3 reaction can be finished well at 8.5 ps, indicating that the gas phase reaction of CH 2 OO + (H 2 O) 3 is not negligible in the atmosphere. Overall, the present results have provided a definitive example of how the favorable hydrolysis of important atmospheric species with (H 2 O) n ( n = 1–4) takes place, which will stimulate one to consider the favorable hydrolysis of water and water clusters with other Criegee intermediates and other important atmospheric species.