sorptive insertion

in surface catalysis
https://doi.org/10.1351/goldbook.S05772
This is analogous to the process of ligand insertion in coordination chemistry. $$\ce{H^{\ast} + C2H4(g) -> ^{\ast}C2H5}$$ This reaction might also be imagined to proceed by adsorption of $\ce{C2H4}$ followed by ligand migration (an associative surface reaction).
Source:
PAC, 1976, 46, 71. (Manual of Symbols and Terminology for Physicochemical Quantities and Units - Appendix II. Definitions, Terminology and Symbols in Colloid and Surface Chemistry. Part II: Heterogeneous Catalysis) on page 84 [Terms] [Paper]