Application of a Novel Linear/Exponential Hybrid Force Field Scaling Scheme to the Longitudinal Raman Active Mode of Polyyne

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• 作者：Shujiang Yang ; Miklos Kertesz ; Viktor Zó ; lyomi ; Jeno Kü ; rti
• 刊名：Journal of Physical Chemistry A
• 出版年：2007
• 出版时间：March 29, 2007
• 年：2007
• 卷：111
• 期：12
• 页码：2434 - 2441
• 全文大小：128K
• 年卷期：v.111,no.12(March 29, 2007)
• ISSN：1520-5215

文摘

The properties of an infinite carbon chain (polyyne), an allotropic form of elemental carbon, are of importancein materials science as well as astronomy. The Raman active longitudinal optical (LO) frequencies are calculatedwith first-principles methods for oligoynes and polyyne and compared with experiments. Since traditionalforce constant scaling schemes fail in this case, we introduced a linear/exponential scaling scheme based onthe exponential behavior of the carbon-carbon bond stretching force constant couplings in quasi-one-dimensional conjugated chains. The LO Raman active frequency is predicted at 1870-1877 cm^-1. Our resultsprovides further evidence for the assignment of the characteristic Raman peaks near 1850 cm^-1 of the recentlydiscovered long linear carbon chains encapsulated inside multiwalled or double-walled carbon nanotubes.