Calculation of the vibrational frequencies of carbon clusters and fullerenes with empirical potentials.
Calculation of the vibrational frequencies of carbon clusters and fullerenes with empirical potentials.
复制标题
具有经验势的碳簇和富勒烯的振动频率的计算。
DOI：
10.1039/c4cp05424e
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Do H
中科院分区：
文献类型：
--
作者：
Do H
给出了用经验碳-碳势计算碳团簇、富勒烯和纳米管的振动频率。对于线性团簇和环状团簇，用反应性经验键序(REBO)势计算的频率与实验最接近。弯曲模式和伸缩模式的平均绝对偏差(MAD)分别为79 cm−1和76 cm−1。非谐性的影响通过二阶振动微扰理论考虑，并倾向于增加弯曲模的频率，而伸缩模在20-60 cm−1范围内有负移，且高频模的移动量较大。这导致了分别为84 cm−1和58 cm−1的弯曲和拉伸模式的MAD。对于富勒烯分子C60，预测的高频模式的谐波频率明显高于实验，这并不能通过考虑非谐性来修正。这种对实验观测频率的高估在计算出的纳米管中G带的频率中也很明显。这表明，对于这些较大的系统，Rebo势并不是最优的，而且在势的范围内调整参数可以得到与实验更接近的结果，特别是如果分开考虑高频和低频模式的话。
Vibrational frequencies for carbon clusters, fullerenes and nanotubes evaluated using empirical carbon–carbon potentials are presented. For linear and cyclic clusters, frequencies evaluated with the reactive empirical bond order (REBO) potential provide the closest agreement with experiment. The mean absolute deviation (MAD) between experiment and the calculated harmonic frequencies is 79 cm−1 for the bending modes and 76 cm−1 for the stretching modes. The effects of anharmonicity are included via second order vibrational perturbation theory and tend to increase the frequency of the bending modes while the stretching modes have negative shifts in the region of 20–60 cm−1, with larger shifts for the higher frequency modes. This results in MADs for the bending and stretching modes of 84 cm−1 and 58 cm−1, respectively. For the fullerene molecule C60, the high frequency modes are predicted to have harmonic frequencies that are significantly higher than experiment, and this is not corrected by accounting for anharmonicity. This overestimation of experimental observed frequencies is also evident in the calculated frequencies of the G band in nanotubes. This suggests that the REBO potential is not optimal for these larger systems and it is shown that adjustment of the parameters within the potential leads to closer agreement with experiment, particularly if higher and lower frequency modes are considered separately.
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DOI：
--
发表时间：
1994
期刊：
Physical Review B (Condensed Matter)
影响因子：
--
作者：
Sanguinetti;Benedek;Righetti;Onida
通讯作者：
Onida
影响因子：
2.3
作者：
Kazim E. Yousaf;P. Taylor
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Kazim E. Yousaf;P. Taylor
[84]富勒烯的两种主要异构体：C84{D2(IV)}和C84{D2d(II)}的振动红外光谱
DOI：
--
发表时间：
2000
期刊：
影响因子：
--
作者：
T. Dennis;M. Hulman;A. Kuzmany;H. Shinohara
通讯作者：
H. Shinohara
C60 中的非简谐振动：由振动自洽场计算得出的势能面
DOI：
--
发表时间：
2005
期刊：
影响因子：
--
作者：
D. A. Jelski;L. Nemes;Allen Broughton
通讯作者：
Allen Broughton
使用自洽电荷密度泛函紧束缚方法精确振动频率
影响因子：
2.8
作者：
E. Malolepsza;H. Witek;K. Morokuma
通讯作者：
K. Morokuma