Theoretical Electronic and Rovibrational Studies for Anions of Interest to the DIBs
Theoretical Electronic and Rovibrational Studies for Anions of Interest to the DIBs
复制标题
DIB 感兴趣的阴离子的理论电子和旋转振动研究
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
R. Fortenberry
中科院分区：
文献类型：
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作者：
R. Fortenberry
摘要亚甲基腈阴离子（CH2CN−）的偶极束缚激发态被认为是803.8 nm处星际扩散带（DIB）的候选载流子。在星际介质（ISM）中检测到了相应的自由基，使阴离子的存在成为可能。这项工作应用了最先进的从头算方法，如耦合簇理论，准确地再现了CH2CN−和类似的亚甲基烯醇阴离子CH2CHO−的电子激发。同样的方法已经被用来表明其他19种阴离子可能具有电子激发态，其中5种是自然界中的价态。同时，为了帮助在ISM中检测这些阴离子，工作也被导向通过使用四次力场（QFFs）预测这些阴离子的振动频率和光谱常数。到目前为止，关于阴离子的理论振转工作包括CH2CN−、C3H−的研究，目前正在进行类似系统的研究。
Abstract The dipole-bound excited state of the methylene nitrile anion (CH2CN−) has been suggested as a candidate carrier for a diffuse interstellar band (DIB) at 803.8 nm. Its corresponding radical has been detected in the interstellar medium (ISM), making the existence for the anion possible. This work applies state-of-the-art ab initio methods such as coupled cluster theory to reproduce accurately the electronic excitations for CH2CN− and the similar methylene enolate anion, CH2CHO−. This same approach has been employed to indicate that 19 other anions may possess electronically excited states, five of which are valence in nature. Concurrently, in order to assist in the detection of these anions in the ISM, work has also been directed towards predicting vibrational frequencies and spectroscopic constants for these anions through the use of quartic force fields (QFFs). Theoretical rovibrational work on anions has thus far included studies of CH2CN−, C3H−, and is currently ongoing for similar systems.