Modelling absorption of electromagnetic radiation by carbon-based constituents of the interstellar medium

这项提议将研究无定形聚集态的碳形成星际物质粒子的假设。这将通过利用无定形碳缺乏长程有序这一众所周知的性质来实现。由于这一性质，非晶态结构对电磁辐射的吸收过程似乎是局部的，类似于分子的吸收过程。因此，将通过从头计算来研究不同形式的小分子碳团簇的电子能谱。这些计算的主要目的将是了解这些小星团吸收电磁辐射的倾向。来自小碳星团的结果将被用来参数化经验的多体势函数，该函数将被用来在比单独使用从头计算更大的范围内检查不同密度的无定形碳的结构。

This proposal will investigate the hypothesis that carbon in an amorphous aggregate state forms particles of interstellar matter. This will be achieved by using the well-known property that amorphous carbon lacks long range order. As a result of this property, the process of absorption of electromagnetic radiation by amorphous structures appears locally and similar to that for molecules. As a result the electronic energy spectra of small molecular clusters of carbon in different forms will be investigated by performing ab initio calculations. A primary purpose of these calculations will be to understand the propensity of these small clusters for absorption of electromagnetic radiation.The results from the small carbon clusters will be used to parameterise an empirical many body potential function which will be used to examine the structure of amorphous carbon of different densities on a much larger scale than can be achieved using ab initio calculations alone.