Compression of curium pyrrolidine-dithiocarbamate enhances covalency

Cyclopentadienyl coordination induces unexpected ionic Am−N bonding in an americium bipyridyl complex

“…Despite these resemblances, prominent differences in the bonding of these elements are observed because of the greater radial extension of the 5 f shell in the actinides, compared to the 4 f shell of the lanthanides 4 – 6 . Covalency is an important aspect of bonding in actinides, largely driven by the hard/soft nature of the ligand and the formal oxidation state of the actinide ion 1 , 5 . Therefore, selective An/Ln separations can be achieved utilizing soft donor ligands, which have demonstrated greater selectivity for actinides over lanthanides due to an increased degree of covalency 7 – 10 .…”

Creation of an unexpected plane of enhanced covalency in cerium(III) and berkelium(III) terpyridyl complexes

“…Unexpected properties, structures, and reactivities emerge in heavy elements because their high nuclear charge accelerates surrounding electrons to relativistic speeds, altering orbital shapes and energies and the nature of chemical bonds 1 . This in turn, leads to abrupt changes in behavior between neighboring elements 2 – 8 and a breakdown of simple descriptions of electronic structure that can be used to explain emerging properties 1 , 9 – 17 . Examples of these discontinuities include the large volume expansion between α-Pu and α-Am, and the corresponding localization of 5 f electrons that leads to superconductivity in α-Am at low temperatures 18 , as well as the diminishment of redox activity that occurs at this same juncture in the actinide series 19 .…”

Synthesis, characterization, and high-pressure studies of a 3D berkelium(iii) carboxylate framework material

“…14,15 The formation of trivalent f-element mellitate crystals can also occur in short time frames suitable for high activity actinide isotopes. 16 Recently, our group has studied a series of trivalent actinide mellitates for plutonium, 17 americium, 18 curium, 19 and californium. 20 The Bk(III) mellitate, Bk 2 [C 6 (CO 2 ) 6 ](H 2 O) 8 Á2H 2 O (Bk1), was obtained by layering a green aqueous solution of BkBr 3 ÁnH 2 O (3.5 mg, 14 mmol 249 Bk 3+ content) and mellitic acid with ethanol.…”

“…S4-S7, ESI †) and were found by single crystal X-ray diffraction to be isostructural with An 2 [C 6 (CO 2 ) 6 ](H 2 O) 8 Á2H 2 O (An = b-Pu, Am, and Cm). [17][18][19] Bk1 crystallizes in the monoclinic space group P2 1 /n (#14) with a three-dimensional framework as shown in Fig. 1.…”