Eur. Phys. J. D 57, 355-364 (2010)
https://doi.org/10.1140/epjd/e2010-00069-8

Density functional theory study of the carbon chains C_nX, C_nX⁺ and C_nX^- (X = O and Se; n = 1–10)

Department of Chemistry, University of Mauritius, 000 Réduit, Mauritius

Corresponding author: ramchemi@intnet.mu

Received: 22 December 2009
Revised: 23 February 2010
Published online: 23 March 2010

Abstract

A theoretical study of C_nX, C_nX⁺ and C_nX^- (X = O and Se; n = 1-10) clusters is carried out employing the density functional theory and the B3LYP functional. All species are fully optimized using the basis set 6-31G(d) for all atoms and further, single-point computations are done using the B3LYP/aug-cc-pVTZ level. Molecular properties such as equilibrium parameters, dipole moment, infrared vibrational frequencies, Raman activities and rotational constant are predicted. The computations indicate that the equilibrium structures are either linear or quasi-linear. We report the different forms of electron affinities, ionization energy, atomization energy and binding energy of the C_nO and C_nSe chains. The results indicate parity effect is very apparent for electron affinity, ionization energy, and binding energy but the effect is less pronounced for atomization energy. The n-even linear chains have larger ionization energy and atomization energy than the n-odd ones but this effect is reversed for electron affinity. The findings from this work are critically discussed and they are very similar to those obtained previously for the hetero-atom doped carbon chains. This research indicates that n-odd carbon chains are more stable than n-even and this is the trend for the chalcogens carbon chains.