Eur. Phys. J. D (2014) 68: 211
https://doi.org/10.1140/epjd/e2014-50186-3

Regular Article

The binding of CO molecule with small W_n(n = 2−9) clusters: a DFT investigation

¹ College of Sciences, Sichuan Agricultural University, Ya’an 625014, P.R. China
² College of Physical Science and Technology, Sichuan University, Chengdu 610064, P.R. China

^a e-mail: sunxy@sicau.edu.cn

Received: 6 March 2014
Received in final form: 10 May 2014
Published online: 7 August 2014

Abstract

The hybrid DFT functional has been utilized to investigate CO adsorption on small W_n(n = 2−9) clusters. The reactivity-selectivity descriptor Δf(r) is proved to be an appropriate tool for predicting the local adsorption site. Our results indicate that the binding of CO to tungsten cluster prefers terminal adsorption mode except for W₃ trimer. The Wiberg bond index can predict the interaction between W atoms and CO molecule to a good accuracy using a linear fit. The dependency on number of adsorbate and charge state of host clusters is also investigated. The high CO coverage seriously weakens the W-CO interaction. The anion cluster reveals the stronger interaction with CO molecule than cation and neutral ones. Moreover, the interesting coverage-dependence is revealed for anion cluster.