“…29,32 While dening Ce 4+ 3d nal state, peaks for 3d 3/2 are labelled as U (901.1 eV), U 00 (907.6 eV), U 000 (916.4 eV) and 3d 5/2 as V (882.3 eV), V 00 (888.4 eV), and V 000 (898.2 eV); similarly for Ce 3+ 3d nal states, U 0 (899.2 eV), U 0 (904.6 eV) and V 0 (880.3 eV), V 0 (886) are the corresponding peaks for 3d 3/2 and 3d 5/2 ionizations, respectively. Doublet designations U 0 /V 0 , U/V, U 0 /V 0 , U 00 /V 00 and U 000 /V 000 are assigned to represent hybridization states of Ce 3d 9 4f 2 O 2p 5 , Ce 3d 9 4f 2 O 2p 4 , Ce 3d 9 4f 1 O 2p 6 , Ce 3d 9 4f 1 O 2p 5 and Ce 3d 9 4f 0 O 2p 6 , respectively.…”