ROMP of COD under equilibrium conditions leads to a complex system of coupl
ed sub-equilibria. Concerning the ring/chain equilibrium, a new concept is
introduced for the description of the course of the ring equilibrium concen
tration as a function of the feed concentration. At the center of this conc
ept is a new specific mark. It is the turning point of the first derivative
of the feed-concentration-dependent ring equilibrium concentration (integr
al as well as individual).