The term is often applied to those sites for @A00155@ which are the effective sites for a particular heterogeneous catalytic reaction. The terms active site and @A00105@ are often used as synonyms, but @A00105@ may also be used to describe an ensemble of sites at which a catalytic reaction takes place.
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 77 [Terms] [Paper]
See also:
PAC, 1992, 64, 143. (Glossary for chemists of terms used in biotechnology (IUPAC Recommendations 1992)) on page 145 [Terms] [Paper]