论文标题
部分可观测时空混沌系统的无模型预测
Computational Estimation of the Binding Energies of POx and HPOx (x=2,3) Species
论文作者
论文摘要
在恒星和行星形成期间气相和固相之间的分子分布决定了气体和晶粒表面化学的轨迹，以及向新生行星传递元件。这种分布主要是由不同分子与水冰表面的结合能设定的。我们在计算上估计了水面上十个天体相关物种物种的结合能，我们还验证了20种具有已知结合能的物种的方法。我们使用DFT计算（M06-2X/AUG-CC-PVDZ）来计算分子和水分子簇的能量（1-3 h $ _2 $ o分子），并通过比较复合物和单独的分子和簇能来确定结合能。我们还可以通过使用实验测量的结合能来首先校准计算方法来探索这些估计方法是否可以改善。使用20个参考分子，我们发现2H $ _2 $ o簇大小可产生最佳的结合能估计，并且在数据中应用校准可能会改善某些类别的分子的结果，包括更多的耐火材料。 Based on these calculations we find that, small P-bearing molecules such as PH$_3$, PN, PO, HPO, PO$_2$ and POOH are relatively volatile and should desorb prior or concomitantly with water ice, while H$_2$PO, HPO$_2$, PO$_3$, PO$_2$OH can strongly bind to any hydroxylated surface, and will likely remain on the星际颗粒晶粒经过水冰的解剖表面。 P载体在谷物上的耗竭构成了将磷分子纳入行星和行星可能性的途径。
The distribution of molecules between the gas and solid phase during star and planet formation, determines the trajectory of gas and grain surface chemistry, as well as the delivery of elements to nascent planets. This distribution is primarily set by the binding energies of different molecules to water ice surfaces. We computationally estimated the binding energies of ten astrochemically relevant P-bearing species on water surface, we also validate our method for 20 species with known binding energies. We used DFT calculations (M06-2X/aug-cc-pVDZ) to calculate the energetics of molecules and water-molecule clusters (1-3 H$_2$O molecules) and from this determined the binding energy by comparing the complex and the separate molecule and cluster energies. We also explore whether these estimates can be improved by first calibrating our computational method using experimentally measured binding energies. Using the 20 reference molecules we find that the 2H$_2$O cluster size yields the best binding energy estimates and that the application of a calibration to the data may improve the results for some classes of molecules, including more refractory species. Based on these calculations we find that, small P-bearing molecules such as PH$_3$, PN, PO, HPO, PO$_2$ and POOH are relatively volatile and should desorb prior or concomitantly with water ice, while H$_2$PO, HPO$_2$, PO$_3$, PO$_2$OH can strongly bind to any hydroxylated surface, and will likely remain on the interstellar grains surface past the desorbtion of water ice. The depletion of P-carriers on grains constitute a pathway for the inclusion of Phosphorous molecules in planets and planetesimals.
