Hui Wallace C H, Lemke Kono H
Department of Earth Sciences, University of Hong Kong, Pokfulam Road, Pok Fu Lam, Hong Kong, SAR.
J Chem Phys. 2020 Aug 28;153(8):084302. doi: 10.1063/5.0015597.
Ozone-water complexes O(HO) (n = 1-2) have been studied using coupled cluster theory with triple excitations CCSD(T) with correlation consistent basis sets aug-cc-pVnZ (n = D, T, Q) and complete basis set (CBS) extrapolation techniques. We identified seven dimer (n = 1) and nine trimer species (n = 2) with open C and cyclic D ozone. Calculations at the CCSD(T)/CBS level of theory for C O(HO) on the counterpoise (CP)-corrected potential energy surface yield a dissociation energy of D = 2.31 kcal/mol and an O central-oxygen (O) HO oxygen (O) distance r[O⋯O] of 3.097 Å, which is in good agreement with an experimental value of 2.957 Å [J. Z. Gillies et al., J. Mol. Spectrosc. 146, 493 (1991)]. Combining our CCSD(T)/CBS value of D for C O(HO) with our best estimate anharmonic CCSD(T)/aVTZ ΔZPE yields a D value of 1.82 kcal/mol; the CCSD(T)/CBS value of D for D O(HO) is 1.51 kcal/mol and yields an anharmonic CCSD(T)/aVTZ D = 0.99 kcal/mol. CCSD(T)/aVTZ dissociation energies and structures for C O(HO) are D = 4.15 kcal/mol, (D = 3.08 kcal/mol) and r[O⋯O] = 2.973 Å, and D = 2.64 kcal/mol (D = 1.68 kcal/mol) with r[O⋯O] = 2.828 Å for D O(HO). The results from ab initio molecular dynamics simulations, which consider dynamic and thermal effects in O(HO), show that the O(HO) complex remains stable at 50 K and dynamically interconverts between two hydrogen-bonded conformers with short O⋯O contacts (3.85 Å). Carr-Parrinello molecular dynamic (CPMD) simulations for O(HO) and O(HO) at 100 K demonstrate that O(HO) remains structurally intact, whereas O(HO) dissociates to free ozone and water, a feature consistent with the larger average binding energy in O(HO) (2.2 kcal/mol) vs that in O(HO) (1.8 kcal/mol). Finally, the results from CCSD(T)/CBS and CPMD simulations demonstrate that the large inter-trimer binding energies in O(HO) would give rise to an elevated trimer/dimer population ratio, making O(HO) a particularly stable and spectroscopically detectable complex.
已使用耦合簇理论中的三激发CCSD(T)方法以及相关一致基组aug-cc-pVnZ（n = D、T、Q）和完全基组（CBS）外推技术，对臭氧 - 水复合物O(HO)（n = 1 - 2）进行了研究。我们确定了具有开环C和环状D臭氧的七种二聚体（n = 1）和九种三聚体物种（n = 2）。在对抵消校正势能面上的C O(HO)进行CCSD(T)/CBS理论水平计算时，得到的解离能D = 2.31 kcal/mol，中心氧原子（O）与羟基氧原子（O）之间的距离r[O⋯O]为3.097 Å，这与实验值2.957 Å [J. Z. Gillies等人，《分子光谱学杂志》146, 493 (1991)] 非常吻合。将我们对于C O(HO)的CCSD(T)/CBS的D值与我们最佳估计的非谐CCSD(T)/aVTZ ΔZPE相结合，得到D值为1.82 kcal/mol；对于D O(HO)的CCSD(T)/CBS的D值为1.51 kcal/mol，得到非谐CCSD(T)/aVTZ D = 0.99 kcal/mol。C O(HO)的CCSD(T)/aVTZ解离能和结构为D = 4.15 kcal/mol，（D = 3.08 kcal/mol）且r[O⋯O] = 2.973 Å，对于D O(HO)，D = 2.64 kcal/mol（D =
