Table 1. O–O Stretching Frequencies of Mononuclear Metal Superoxo Complexesa.
| complex | ν(16O–16O), cm–1 | ν(18O–18O), cm–1 | Δν(O–O), cm–1 | ref |
|---|---|---|---|---|
| 2 | 1125, 1145 | 1073 | 62 | this work |
| 2′ | 1125, 1145 | 1064, 1078 | 61 | this work |
| [MnIIIL(O2•–)(H2O)](PF6)2 | 1124 | 1035 | 89 | (19) |
| 3 | 1125 | 1062 | 63 | (14) |
| 4 | 1135 | 1070 | 65 | (16) |
| [FeIII(TAML)(η2-O2•–)]2– | 1260 | 1183 | 77 | (15) |
| FeIII(TpMe2)(LPh)(O2•–) | 1168 | 1090 | 78 | (17) |
| CoIII(TpMe2)(LPh)(η1-O2•–) | 1150 | 1090 | 60 | (17) |
| CoIII(salen)(py)(O2•–) | 1144 | 1082 | 62 | (18) |
| [CuII(TMG3tren)(η1-O2•–)]+ | 1117 | 1059 | 58 | (21) |
| [CuII(6-pivTPA)(O2•–)]+ | 1130 | 1067 | 63 | (22) |
| [CrIII (14-TMC)(η1-O2•–)(Cl)]+ | 1170 | 1104 | 66 | (23) |
a
L = 5,11,17,23-tetrakis(trimethylammonium)-25,26,27,28-tetrahydroxycalix[4]arene; TAML = 3,3,6,6,9,9-hexametyl-2,5,7,10-tetraoxo-3,5,6,7,9,10-hexahydro-2H-benzo[e][1,4,7,10]tetraazacyclotridecine-1,4,8,11-tetraide; TpMe2 = hydro-tris(3,5-dimethylpyrazolyl)borate; LPh = bis(2-N-methylimizadolyl)methylphenylborate; salen = N,N′-ethylene-bis(salicylideneiminato); TMG3tren = 1,1,1-tris(1-tetramethylguanidino)]ethyl)amine); 6-pivTPA = (6-pivaloyl-amidopyridyl-2-methyl)bis(6-methylpyridyl-2-methyl)amine; 14-TMC = 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclo-tetradecane.