Free energy profiles for monomer capture in Grubbs- and SHOP-type olefin polymerization catalysts: A constraint ab initio molecular dynamics study. - Sheng-Yong Yang; Ming-Li Xiang; Li-Juan Chen; Guo-Bin Xie; Bing Shi; Yu-Quan Wei; Tom Ziegler (J. Comput. Chem., 2007)