A G3 study of the structure of carbon-nitrogen nanoclusters.
A G3 study of the structure of carbon-nitrogen nanoclusters.
复制标题
碳氮纳米团簇结构的 G3 研究。
DOI：
10.1021/jp105390c
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
M. Hochlaf
中科院分区：
文献类型：
--
作者：
M. M. Al Mogren;A. El;Wad. Z. Alkiali;M. Hochlaf
在合适的情况下，预测了中性、阴离子和阳离子在单线态、双线态和三重态下可能形成的C(m)N(N) （m = 1-4, N = 1-4, m + N = 2-5）形式的碳氮团簇结构。计算在G3、MP2(fc)/6-311+G*和B3LYP/6-311+G*理论水平下进行。计算了与实验数据相关的几个分子性质，如电子能量、平衡几何形状、结合能、HOMO-LUMO间隙（HLG）和自旋污染。此外，还计算了中性团簇的垂直电子附着、绝热电子亲和和垂直电离能。预测的最低能结构大部分为线性结构，而随着簇大小和N原子数的增加，弯曲结构变得更加稳定。在大多数预测的最低能结构中，N原子倾向于乙炔键的末端位置。预测簇的计算BE随着中性簇和阳离子簇的增大而增大，而阴离子簇的计算BE随着簇大小的增大而减小。预测团簇的HLG平均约为11 eV，阴离子团簇的HLG小于中性和阳离子团簇。因此，阴离子团簇的稳定性低于相应的中性和阳离子团簇。最后，对N(2)损失反应进行处理。
Possible structures of the carbon-nitrogen clusters of the form C(m)N(n) (m = 1-4, n = 1-4, m + n = 2-5) were predicted for the neutral, anion, and cation species in the singlet, doublet, and triplet states, whenever appropriate. The calculations were performed at the G3, MP2(fc)/6-311+G*, and B3LYP/6-311+G* levels of theory. Several molecular properties related to the experimental data--such as the electronic energy, equilibrium geometry, binding energy, HOMO-LUMO gap (HLG), and spin contamination --were calculated. In addition the vertical electron attachment, the adiabatic electron affinity, and vertical ionization energy, of the neutral clusters were calculated. Most of the predicted lowest energy structures were linear, whereas bent structures became more stable with the increase of the cluster size and increase of the number of the N atoms. In most of the predicted lowest energy structures, the N atom prefers the terminal position with acetylenic bond. The calculated BE of the predicted clusters increases with the increase of the cluster size for the neutral and cation clusters but decreases with the increase of the cluster size for the anion clusters. The predicted clusters are characterized by high HLG of about 11 eV on the average, with that of the anion clusters is smaller than that for the neutral and cation clusters. It is concluded then that the anion clusters are less stable than the corresponding neutral and cation clusters. Finally, the N(2) loss reaction is treated.