Department of Chemistry, University of Nevada Las Vegas, Las Vegas, Nevada 89154, USA.
J Chem Phys. 2013 Nov 21;139(19):194305. doi: 10.1063/1.4830398.
Quantum scattering calculations are reported for state-to-state vibrational relaxation and reactive scattering in O + OH(v = 2 - 3, j = 0) collisions on the electronically adiabatic ground state (2)A'' potential energy surface of the HO2 molecule. The time-independent Schrödinger equation in hyperspherical coordinates is solved to determine energy dependent probabilities and cross sections over collision energies ranging from ultracold to 0.35 eV and for total angular momentum quantum number J = 0. A J-shifting approximation is then used to compute initial state selected reactive rate coefficients in the temperature range T = 1 - 400 K. Results are found to be in reasonable agreement with available quasiclassical trajectory calculations. Results indicate that rate coefficients for O2 formation increase with increasing the OH vibrational level except at low and ultralow temperatures where OH(v = 0) exhibits a slightly different trend. It is found that vibrational relaxation of OH in v = 2 and v = 3 vibrational levels is dominated by a multi-quantum process.
量子散射计算报告了 O + OH（v = 2-3，j = 0）碰撞在 HO2 分子的电子绝热基态（2）A''势能面上的振动弛豫和反应散射的态态。在超球坐标中求解时不变薛定谔方程，以确定碰撞能量从超冷到 0.35 eV 以及总角动量量子数 J = 0 范围内的能量相关概率和截面。然后使用 J 移近似来计算温度范围 T = 1-400 K 下初始态选择的反应速率系数。结果与现有的准经典轨迹计算结果吻合良好。结果表明，O2 形成的速率系数随 OH 振动能级的增加而增加，但在低温和超低温下，OH（v = 0）表现出略有不同的趋势。发现 OH 在 v = 2 和 v = 3 振动能级中的振动弛豫主要由多量子过程主导。
