Activated adsorption of CO on yttrium clusters Wenjie Zhao, Xingfu Li, Xingli Shao, Bin Xu and Jiangang Yao Eur. Phys. J. D, 67 8 (2013) 186 Published online: 29 August 2013 DOI: 10.1140/epjd/e2013-40073-x