First-principles calculation of the Peierls distortion in an infinite linear carbon chain: the contribution of Raman spectroscopy
Article first published online: 14 DEC 2007
Copyright © 2007 John Wiley & Sons, Ltd.
Journal of Raman Spectroscopy
Special Issue: Proceedings of the XX Italian Conference on Raman Spectroscopy and Non Linear Effects Catania, Italy, 27 - 29 June 2007
Volume 39, Issue 2, pages 164–168, February 2008
How to Cite
Milani, A., Tommasini, M., Fazzi, D., Castiglioni, C., Zoppo, M. D. and Zerbi, G. (2008), First-principles calculation of the Peierls distortion in an infinite linear carbon chain: the contribution of Raman spectroscopy. J. Raman Spectrosc., 39: 164–168. doi: 10.1002/jrs.1850
- Issue published online: 29 JAN 2008
- Article first published online: 14 DEC 2007
- Manuscript Accepted: 21 JUL 2007
- Manuscript Received: 14 JUN 2007
- Italian Ministry of Education, University and Research. Grant Number: RBNE033KMA
- Peierls distortion;
- DFT calculations;
The modulation of the longitudinal optical (LO) phonon branch of a linear, infinite carbon chain (carbyne) by the degree of bond length alternation (BLA) is discussed in relation to the wavenumber dispersion of the strongest Raman line of oligoynes. Furthermore, the potential energy surface describing the Peierls distortion of the infinite 1D crystal has been determined theoretically through DFT calculations with periodic boundary conditions. A two-minima potential surface has been obtained as a function of BLA parameter, under the constraint that the diatomic unit cell keeps its translational period fixed to the optimized value. In this way, it has been possible to obtain the generalized harmonic force constant associated with the LO phonon at the Γ point. The results obtained can be related to the observed behavior of the LO Raman line upon the temperature-driven phase transition towards a cumulenic structure. Copyright © 2007 John Wiley & Sons, Ltd.