Figure 9
(a) [UO 2 (OH 2 ) 4 ]2+-H 2 Cat•28(H 2 O) singlet (=UO 2 -H 2 Cat), (b) [UO(OH)(OH 2 ) 4 ]+-HCat•28(H 2 O) triplet (=UO 2 -HCat), (c) [U(OH) 2 (OH 2 ) 4 ]-Cat•28(H 2 O) quintet (=U(OH) 2 -Cat), (d) outer-sphere [UO 2 (OH 2 ) 4 ]2+-H 2 Cat•28(H 2 O) (=UO 2 -H 2 Cat OS), (e) U(OH) 2 (OH 2 ) 4 (C 6 H 4 O 2 )•28(H 2 O) (=U(OH) 2 -Quin). Note the single bond to catechol in (a) and the H transfer to the axial uranyl O atoms in (b) concomitant with the changing electronic state and uranyl reduction (Table 3). The most stable state calculated is (e) where the uranyl has been reduced and a quinone has generated. This result is consistent with the experimental observations of [100] presuming that the U(IV) produced in this reaction was re-oxidized by O2 in these aerobic experiments.