Braams Bastiaan J, Yu Hua-Gen
Department of Mathematics and Computer Science, Emory University, Atlanta, Georgia 30322, USA.
Phys Chem Chem Phys. 2008 Jun 7;10(21):3150-5. doi: 10.1039/b801928b. Epub 2008 Apr 8.
An analytic potential energy surface has been constructed by fitting to about 28 thousand energy points for the electronic ground-state (X (2)A'') of HO(3). The energy points are calculated using a hybrid density functional HCTH and a large basis set aug-cc-pVTZ, i.e., a HCTH/aug-cc-pVTZ density functional theory (DFT) method. The DFT calculations show that the trans-HO(3) isomer is the global minimum with a potential well depth of 9.94 kcal mol(-1) with respect to the OH + O(2) asymptote. The equilibrium geometry of the cis-HO(3) conformer is located 1.08 kcal mol(-1) above that of the trans-HO(3) one with an isomerization barrier of 2.41 kcal mol(-1) from trans- to cis-HO(3). By using this surface, a rigorous quantum dynamics (QD) study has been carried out for computing the rovibrational energy levels of HO(3). The calculated results determine a dissociation energy of 6.15 kcal mol(-1), which is in excellent agreement with the experimental value of Lester et al. [J. Phys. Chem. A, 2007, 111, 4727.].
通过拟合HO(3)电子基态（X (2)A''）的约28000个能量点，构建了一个解析势能面。这些能量点是使用混合密度泛函HCTH和大基组aug-cc-pVTZ计算得到的，即HCTH/aug-cc-pVTZ密度泛函理论（DFT）方法。DFT计算表明，反式HO(3)异构体是全局最小值，相对于OH + O(2)渐近线，势阱深度为9.94 kcal mol(-1)。顺式HO(3)构象异构体的平衡几何结构比反式HO(3)的平衡几何结构高1.08 kcal mol(-1)，从反式到顺式HO(3)的异构化势垒为2.41 kcal mol(-1)。利用这个势能面，进行了严格的量子动力学（QD）研究，以计算HO(3)的振转能级。计算结果确定解离能为6.15 kcal mol(-1)，这与Lester等人的实验值[《物理化学杂志A》，2007年，111卷，4727页]非常吻合。
