as a service to our authors and readers , this journal provides supporting information supplied by the authors .
such materials are peer reviewed and may be reorganized for online delivery , but are not copyedited or typeset .
technical support issues arising from supporting information ( other than missing files ) should be addressed to the authors .
 abstractthe kinetics of formation of the valence tautomers ( tpfc)mniv(ola)]n+ [ where la = znii , caii , sciii , ybiii , b(c6f5)3 , and trifluoroacetic acid ( tfa ) ; tpfc=5,10,15tris(pentafluorophenyl ) corrole ] from ( tpfc)mnv(o ) were followed by uv / vis spectroscopy , giving secondorder rate constants ranging over five orders of magnitude from 102 for ca to 103 
 m 
 1  s1 for sc . 
 hydrogen atom transfer ( hat ) rates from 2,4ditertbutyl phenol ( 2,4dtbp ) to the various lewis acid valence tautomers of manganese oxo corrole complexes were evaluated and compared . for la = tfa , 
 sciii , or ybiii , the rate constants of hat were comparable to unactivated ( tpfc)mnv(o ) . 
 however , with la = b(c6f5)3 , znii , and caii , 6 , 21 , and 31fold rate enhancements were observed , respectively . remarkably , [ ( tpfc)mniv(oca)]2 + gave the most enhancement despite its rate of formation being the slowest . 
 comparisons of hat rate constants among the various lewis acid tautomers revealed that both size and charge are important . 
 this study underscores how valence may affect the reactivity of highvalent manganeseoxo compounds and sheds light on nature 's choice of ca in the activation of mnoxo in the oxygenevolving complex . 
Supporting information