Theoretical insights on the complexation of Am(III) and Cm(III) with amide-type ligands

  • Cong-Zhi Wang
  • Jian-Hui Lan
  • Qun-Yan Wu
  • Zhi-Fang Chai
  • Wei-Qun ShiEmail author


Separation of adjacent actinides (An) americium and curium is a critical and challenging step in advanced nuclear fuel cycles. Herein, we performed a quantum chemical calculation to explore the separation behavior of Am(III) from Cm(III) by two representative amide-type ligands, N,N′-dimethyl-N,N′-dioctyl-2-(2-hexyloxyethyl)malonamide (DMDOHEMA) and N,N,N′,N′,N″,N″-hexaalkyl-nitrilotriacetamide (NTAamide). It was found that the better energy match of Am 5f orbitals and O, N 2p orbitals of the amide-type ligands resulted in the selective ability of these ligands to Am3+ over Cm3+. Complexation reaction analysis predicted that An(DMDOHEMA)2(NO3)3 and [An(NTAamide)2]3+ were the most probable species in the separation processes.


Actinides Separation Extraction Density functional theory 



This work was supported by the National Natural Science Foundation of China (Grant Nos. 21876174, 11875058, 11575212), Major Program of the National Natural Science Foundation of China (21790373), and the Science Challenge Project (TZ2016004). The results described in this study were obtained on the ScGrid of the Supercomputing Center, Computer Network Information Center of Chinese Academy of Sciences.

Supplementary material

10967_2019_6804_MOESM1_ESM.docx (915 kb)
Supplementary material 1 (DOCX 914 kb)


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  1. 1.Laboratory of Nuclear Energy Chemistry, Institute of High Energy PhysicsChinese Academy of SciencesBeijingChina
  2. 2.Engineering Laboratory of Advanced Energy Materials, Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingboChina

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