biostudies-literatureConour CSOffice of Science, Government of Western Australia280https://www.ebi.ac.uk/biostudies/studies/S-EPMC12475471biostudies-literatureUnknown8(1)The study of actinide electronic structure and bonding within rigorously controlled environments is fundamental to advancing nuclear applications. Here, we report a new set of isostructural actinide organometallics; An(COT^big)₂, (An = Th, U, Np, and Pu), where COT^big is the bulky 1,4-bis(triphenylsilyl)-substituted cyclooctatetraenyl dianion (1,4-(Ph₃Si)₂C₈H₆)^2-. The actinide(IV) metallocene sandwiches have a clam-shell structure, offering a new molecular symmetry to explore f-orbital contributions in bonding. Combined experimental and computational studies reveal that An(COT^big)₂ complexes strongly differ from the previously published coplanar An(COT)₂ sandwiches due toCommunications chemistryTrends in actinide electronic structure revealed from asymmetric, isostructural transuranic metallocenes.PMC12475471DE-AC02-05CH11231Conour CSWoods JJPyrch MMFKeener MRAutschbach JKatzer NJSen AArnold PLfalseTrends in actinide electronic structure revealed from asymmetric, isostructural transuranic metallocenes.The study of actinide electronic structure and bonding within rigorously controlled environments is fundamental to advancing nuclear applications. Here, we report a new set of isostructural actinide organometallics; An(COT^big)₂, (An = Th, U, Np, and Pu), where COT^big is the bulky 1,4-bis(triphenylsilyl)-substituted cyclooctatetraenyl dianion (1,4-(Ph₃Si)₂C₈H₆)^2-. The actinide(IV) metallocene sandwiches have a clam-shell structure, offering a new molecular symmetry to explore f-orbital contributions in bonding. Combined experimental and computational studies reveal that An(COT^big)₂ complexes strongly differ from the previously published coplanar An(COT)₂ sandwiches due to2025-01-01T00:00:00Z2025 Sep2026-06-03T23:05:27.076Z2026-05-31T03:07:06.314ZS-EPMC124754714100676210.1038/s42004-025-01646-4