The interactions between HCl and both the pristine and defect {111}, {110} and {100} surfaces of PuO₂ are modelled using hybrid density functional theory, within the periodic electrostatic embedded cluster method. In the case of the pristine surfaces, adsorptions onto the {110} surface are the most stable, likely due in part to the presence of surface hydrogen bonds. In addition, results suggest that even when dissociatively adsorbed onto the surface, the proximity of the hydrogen and chlorine atoms has a significant impact on the stability of the system. The electronic structure of both the pristine and reduced surfaces of PuO₂ and UO₂ is also probed, with unpaired electrons left behind in a neutral oxygen vacancy defect site having a greater tendency to delocalize on the surface of UO₂ than PuO₂. HCl adsorptions on the reduced surfaces reveal that configurations in which the chlorine atom attempts to “heal” the gap left by the oxygen vacancy in the {111} surface are by far the most stable of all considered. Finally, molecular thermodynamics is employed to translate adsorption energies to HCl thermal desorption temperatures, for each geometry considered. Particularly when a chlorine atom is embedded in the surface of PuO₂, the temperatures required for thermal desorption to occur are high, implying that although thermal treatment is likely to remove some chlorine contamination from PuO₂ samples, some will likely remain bound to defect sites within the material.

在周期性静电嵌入簇方法中，使用混合密度泛函理论对HCl与PuO ₂的原始表面和缺陷{111}，{110}和{100}表面之间的相互作用进行建模。在原始表面的情况下，在{110}表面的吸附是最稳定的，这可能部分是由于表面氢键的存在所致。另外，结果表明，即使解离地吸附到表面上，氢和氯原子的接近也对系统的稳定性有重大影响。PuO ₂和UO ₂的原始表面和还原表面的电子结构还探测到，在中性氧空位缺陷位点留下的未配对电子比PuO ₂具有更大的在UO ₂表面离域的趋势。还原表面上的HCl吸附表明，到目前为止，考虑到其中氯原子试图“修复” {111}表面中氧空位所留下的间隙的构型是最稳定的。最后，对于每种几何形状，都采用分子热力学将吸附能转化为HCl热脱附温度。特别是当氯原子嵌入PuO ₂的表面时，发生热脱附所需的温度很高，这意味着尽管进行热处理可能会从PuO中去除一些氯污染。_2个样品中，有些样品可能会保留在材料中的缺陷部位上。