1 ICS Iron-sulfur-molybdenum cluster with interstitial carbon 1.000 2 CFM Fe-mo-S cluster 0.944 3 ICE Iron-sulfur-molybdenum cluster with interstitial carbon 0.944 4 ICG Iron-sulfur-molybdenum cluster with interstitial carbon with selenium incorporated 0.895 5 S5Q Fefe cofactor 0.895 6 ICZ Iron-sulfur-molybdenum cluster with interstitial carbon 0.889 7 8P8 C fe7 s8 V 0.842 8 D6N Fev 0.750 9 ICH Iron-sulfur-molybdenum cluster with interstitial carbon with selenium incorporated 0.714