Berkelium–carbon bonding in a tetravalent berkelocene

Russo, Dominic R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000340149216); Gaiser, Alyssa N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017063359X); Price, Amy N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)]; Sergentu, Dumitru-Claudiu [Alexandru Ioan Cuza University (Romania)] (ORCID:0000000165705245); Wacker, Jennifer N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000154111986); Katzer, Nicholas [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0009000184513676); Peterson, Appie A. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000228247545); Branson, Jacob A. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000235230303); Yu, Xiaojuan [Univ. at Buffalo, NY (United States)] (ORCID:0000000194126170); Kelly, Sheridon N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000309996919); Ouellette, Erik T. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000321386259); Arnold, John [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:000000019671227X); Long, Jeffrey R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000253241321); Lukens, Wayne W. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)]; Teat, Simon J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000195152602); Abergel, Rebecca J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000239068761); Arnold, Polly L. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000164105838); Autschbach, Jochen [Univ. at Buffalo, NY (United States)] (ORCID:000000019392877X); Minasian, Stefan G. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000313467497)

doi:10.1126/science.adr3346

DOE OSTI · 2571277

Berkelium–carbon bonding in a tetravalent berkelocene

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Abstract

Interest in actinide–carbon bonds has persisted since actinide organometallics were first investigated for applications in isotope separation during the Manhattan Project. Transplutonium organometallics are rarely isolated and structurally characterized, likely owing to limited isotope inventories, a scarcity of suitable laboratory infrastructure, and intrinsic difficulties with the anaerobic conditions required. In this paper, we report the discovery of an organometallic “berkelocene” complex prepared from 0.3 milligrams of berkelium-249. Single-crystal x-ray diffraction shows a tetravalent berkelium ion between two substituted cyclooctatetraene ligands, resulting in the formation of berkelium–carbon bonds. The coordination in berkelocene resembles that of uranocene, and calculations show that the berkelium 5f orbitals engage in covalent overlap with the δ-symmetry orbitals of the cyclooctatetraenide ligand π system. Charge transfer from the ligands is diminished relative to uranocene and other actinocenes, which maximizes contributions from the stable, half-filled 5f 7 configuration of tetravalent berkelium.

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Russo, Dominic R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000340149216), Gaiser, Alyssa N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:000000017063359X), Price, Amy N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)], Sergentu, Dumitru-Claudiu [Alexandru Ioan Cuza University (Romania)] (ORCID:0000000165705245), Wacker, Jennifer N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000154111986), Katzer, Nicholas [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0009000184513676), Peterson, Appie A. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000228247545), Branson, Jacob A. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000235230303), Yu, Xiaojuan [Univ. at Buffalo, NY (United States)] (ORCID:0000000194126170), Kelly, Sheridon N. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000309996919), Ouellette, Erik T. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000321386259), Arnold, John [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:000000019671227X), Long, Jeffrey R. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000253241321), Lukens, Wayne W. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)], Teat, Simon J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States). Advanced Light Source (ALS)] (ORCID:0000000195152602), Abergel, Rebecca J. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000239068761), Arnold, Polly L. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)] (ORCID:0000000164105838), Autschbach, Jochen [Univ. at Buffalo, NY (United States)] (ORCID:000000019392877X), Minasian, Stefan G. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)] (ORCID:0000000313467497). 2025-02-27. Berkelium–carbon bonding in a tetravalent berkelocene. https://doi.org/10.1126/science.adr3346

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