Tan Xiaofeng
X Scientific, Inc., 1000 Kiely Boulevard Unit 90, Santa Clara, CA 95051, United States.
Spectrochim Acta A Mol Biomol Spectrosc. 2009 Jan;71(5):2005-11. doi: 10.1016/j.saa.2008.07.038. Epub 2008 Aug 3.
A theoretical approach is developed to pre-select individual polycyclic aromatic hydrocarbons (PAHs) as possible carriers of the diffuse interstellar bands (DIBs). In this approach, a computer program is used to enumerate all PAH molecules with up to a specific number of fused benzene rings. Fast quantum chemical calculations are then employed to calculate the electronic transition energies, oscillator strengths, and rotational constants of these molecules. An electronic database of all PAHs with up to any specific number of benzene rings can be constructed this way. Comparison of the electronic transition energies, oscillator strengths, and rotational band contours of all PAHs in the database with astronomical spectra allows one to constrain the identities of individual PAHs as possible carriers of some of the intense narrow DIBs. Using the current database containing up to 10 benzene rings we have pre-selected 8 closed-shell PAHs as possible carriers of the famous lambda6614 DIB.
本文提出了一种理论方法，用于预先筛选出作为弥散星际带（DIBs）可能载体的单个多环芳烃（PAHs）。在该方法中，使用计算机程序枚举具有特定数量稠合苯环的所有PAH分子。然后采用快速量子化学计算来计算这些分子的电子跃迁能量、振子强度和转动常数。通过这种方式，可以构建一个包含任意特定数量苯环的所有PAHs的电子数据库。将数据库中所有PAHs的电子跃迁能量、振子强度和转动带轮廓与天文光谱进行比较，能够限制单个PAHs作为某些强窄DIBs可能载体的身份。利用当前包含多达10个苯环的数据库，我们已经预先筛选出8种闭壳PAHs作为著名的λ6614 DIB的可能载体。
