发表机构
University of Antwerp; University of Montana（安特卫普大学; 蒙大拿大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
研究冰充电对非晶态固态水上星际含硫物种天体化学的影响，通过密度泛函理论计算束缚能分布，发现中性和带电ASW上含硫分子束缚能变化有不同情况，与分子性质相关。
AI 中文摘要
我们旨在推导中性和带负电的非晶态固态水（ASW）上原子S以及含硫分子H₂S、SO₂和OCS的具有统计稳健性和物理可解释性的束缚能（BE）分布，并评估过量负电荷如何改变它们的保留以及在冷致密分子云硫库中的潜在作用。通过密度泛函理论（DFT）使用ORCA软件计算S、SO₂、OCS和H₂S的基组叠加误差（BSSE）和零点能（ZPE）校正的BE。首先从对中性和带电小水络合物的基准计算中针对耦合簇参考能量选择特定分子的DFT理论水平，然后将所选协议应用于研究在中性和带电ASW簇上的吸附。在五个独立的非晶冰簇上采样了一系列吸附位点，得出考虑ASW位点异质性的BE分布。中性ASW产生与先前水冰估计一致的宽泛、依赖位点的BE分布。在带电ASW上，确定了三种一般情况：BE要么由于电子转移总是增加（S原子、SO₂），BE略有增加但无电子转移（H₂S），要么除非在特定条件下发生电子转移BE保持不变（OCS）。这些发现与这些分子的分子性质内在相关。
英文摘要
We aim to derive statistically robust and physically interpretable BE distributions for atomic S and the sulfur-bearing molecules H$_2$S, SO$_2$, and OCS on neutral and negatively charged ASW, and assess how excess negative charge alters their retention and potential role in the sulfur reservoir of cold dense molecular clouds. Basis set superposition error (BSSE) and zero-point energy (ZPE) corrected BEs of S, SO$_2$, OCS and H$_2$S, are calculated by density functional theory (DFT), using the ORCA software. Molecule-specific DFT levels of theory were first selected from benchmark calculations on neutral and charged small water complexes, against coupled-cluster reference energies. The selected protocols were then applied to study adsorption on neutral and charged ASW clusters. A range of adsorption sites were sampled on five independent amorphous ice clusters, yielding BE distributions that account for the site heterogeneity of ASW. Neutral ASW yields broad, site-dependent BE distributions consistent with previous water-ice estimates. On charged ASW, three general cases are identified: the BE will either always increase due to electron transfer (S-atom, SO$_2$), the BE increases slightly without any electron transfer (H$_2$S) or the BE remains the same unless an electron transfer occurs under specific conditions (OCS). These findings are inherently linked to the molecular properties of these molecules.
DOI：10.1051/0004-6361/202661939
