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Xu L, Zhao XK, Cao H, Hu HS, Li J, Chen J, Xu C. Complexation of Hexavalent Neptunium(VI) with Oxydiacetic Acid and Its Amide Derivatives in Aqueous Solution: Spectrophotometry and DFT Calculations. Inorg Chem 2024; 63:6173-6183. [PMID: 38530927 DOI: 10.1021/acs.inorgchem.3c04221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Unfolding the solution coordination chemistry of high-valent transuranium elements with the "CHON"-type ligands is important to understand the fundamental chemistry of actinides and to design more efficient extractants for partitioning of transuranium elements in advanced nuclear fuel cycles. Here, the complexation of a hexavalent neptunyl ion (NpO22+ or Np(VI)) with oxydiacetic acid (ODA) has been systematically investigated in comparison with its amide analogues N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) and N,N,N',N'-tetramethyl-3-oxa-glutaramide (TMOGA) both experimentally and computationally. The formation of both 1:1 and 1:2 complexes between Np(VI) and the three ligands was identified by spectrophotometry, and their stability constants were obtained and compared with those of hexavalent U(VI) and Pu(VI). The corresponding bonding nature is elucidated by using energy decomposition analysis (EDA), electrostatic potential (ESP), ELF contours, and natural orbitals for chemical valence (NOCV) methods, which shows that the Np-O bonds are essentially ionic in character and the unoccupied 6d orbitals of Np play a key role in enhancing the covalent interactions between Np(VI) and the three ligands.
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Affiliation(s)
- Lei Xu
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
- Institute of Nuclear Agricultural Science, Key Laboratory of Nuclear Agricultural Sciences of Ministry of Agriculture and Zhejiang Province, Zhejiang University, Hangzhou 310058, China
| | - Xiao-Kun Zhao
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - Hong Cao
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Han-Shi Hu
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Jun Li
- Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Jing Chen
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Chao Xu
- Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
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2
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Parimi A, Mosher E, Schreckenbach G. Periodic trends in trivalent actinide halides, phosphates, and arsenates. Dalton Trans 2023; 52:18035-18044. [PMID: 37987618 DOI: 10.1039/d2dt02725a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
Due to the limited abundance of the actinide elements, computational methods, for now, remain an exclusive avenue to investigate the periodic trends across the actinide series. As every actinide element can exhibit a +3-oxidation state, we have explored model systems of gas-phase actinide trihalides, phosphates, and arsenates across the series to capture the periodic trends. By doing so, we were able to capture the periodic trends down the halogen series as well, and for the first time we are reporting a study on actinide astatides. Using scalar and spin-orbit relativistic Density Functional Theory (DFT) calculations, we have explored the variations in bond lengths, bond angles, and the charges on actinides (An). Despite the use of different sets of ligands, the trends remain similar. The properties of trivalent Pa, U, Np, and Pu are nearly identical; similar ionic radii could be the reason. The actinide elements show a tendency to exhibit a pre-Pu and a post-Cm behaviour, with Am acting as a switch. This could be due to the change in the behaviour from d-f-type to f-filling/d-type at around Pu-Cm in the actinides as already proposed in the previous literature. Bond lengths in the AnX3 increase down the halide series, and the atomic charges decrease on the actinide elements.
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Affiliation(s)
- Ashutosh Parimi
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - Emmalee Mosher
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
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3
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Jennifer G A, Gao Y, Schreckenbach G, Varathan E. Periodic Trends in the Stabilization of Actinyls in Their Higher Oxidation States Using Pyrrophen Ligands. Inorg Chem 2023; 62:6920-6933. [PMID: 37104857 DOI: 10.1021/acs.inorgchem.3c00022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Owing to the prominent existence and unique chemistry of actinyls, their complexation with suitable ligands is of significant interest. The complexation of high-valent actinyl moieties (An = U, Np, Pu and Am) with the acyclic sal-porphyrin analogue called "pyrrophen" (L(1)) and its dimethyl derivative (L(2)) with four nitrogen and two oxygen donor atoms was studied using relativistic density functional theory. Based on the periodic trends, the [UVO2-L(1)/L(2)]1- complexes show shorter bond lengths and higher bond orders that increase across the series of pentavalent actinyl complexes mainly due to the localization of the 5f orbitals. Among the hexavalent complexes, the [UVIO2-L(1)/L(2)] complexes have the shortest bonds. Following the uranyl complex, due to the plutonium turn, the [AmVIO2-L(1)/L(2)] complexes exhibit comparable properties with those of the former. Charge analysis suggests the complexation to be facilitated through ligand-to-metal charge transfer (LMCT) mainly through σ donation. Thermodynamic feasibility of complexation was modeled using hydrated actinyl moieties in aqueous medium and was found to be spontaneous. The dimethylated pyrrophen (L(2)) shows higher magnitudes of thermodynamic parameters indicating increased feasibility compared to the unsubstituted ligand (L(1)). Energy decomposition analysis (EDA) along with extended transition-state-natural orbitals for chemical valence theory (ETS-NOCV) analysis shows that the dominant electrostatic contributions decrease across the series and are counteracted by Pauli repulsion. Slight but considerable covalency is provided to hexavalent actinyl complexes by orbital contributions; this was confirmed by molecular orbital (MO) analysis that suggests strong covalency in americyl (VI) complexes. In addition to the pentavalent and hexavalent actinyl moieties, heptavalent actinyl species of neptunyl, plutonyl, and americyl were studied. Beyond the influence of the charges, the geometric and electronic properties point to the stabilization of neptunyl (VII) in the pyrrophen ligand environment, while the others shift to a lower (+VI) and relatively stable OS on complexation.
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Affiliation(s)
- Abigail Jennifer G
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur 603203, Tamil Nadu, India
| | - Yang Gao
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
- NHC Key Laboratory of Nuclear Technology Medical Transformation (Mianyang Central Hospital), Mianyang 621010, China
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Elumalai Varathan
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur 603203, Tamil Nadu, India
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4
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Wang C, Hu SX, Zhang L, Wang K, Liu HT, Zhang P. Trends in the Electronic Structure and Chemical Bonding of a Series of Porphyrinoid-Uranyl Complexes. Inorg Chem 2023; 62:5376-5386. [PMID: 36990449 DOI: 10.1021/acs.inorgchem.2c03986] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
In this paper, we have explored the relativistic density functional theory study on a series of deprotonated porphyrinoid (Ln) complexes of uranyl to investigate the geometrical structures and chemical bonding. The ligands bound with uranyl in the 1:1 complexes [UO2(Ln)]x (n = 4, 5, 6; x = 0, -1, -2), showing more thermodynamic stability for "in-cavity" structures of L5 and L6 than that of the "side-on" structure of L4 and an increase in stability with the increase of negative charges, L2- < L3- < L4-. Among the six ligands, the cyclo[6]pyrrole presents the best selectivity toward uranyl. Based on chemical bonding analyses, the U-NL bond in the in-cavity complexes adopts a typical dative NL → U bond with mainly ionic bonding and significant covalency, which comes from the significant orbital interaction of U 5fϕ6dδ7s hybrid AOs and NL 2p-based MOs. This work provides a systematic understanding of the coordination chemistry in uranyl pyrrole-containing macrocycle complexes and the nature of chemical bonding in such systems, which may provide inspirations for the future design of synthetic targets that could be relevant to actinide separations or in the remediation of spent nuclear fuel.
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Affiliation(s)
- Cong Wang
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Hebei University, Baoding 071002, China
| | - Shu-Xian Hu
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Lu Zhang
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Kai Wang
- Hebei Key Lab of Optic-electronic Information and Materials, The College of Physics Science and Technology, Hebei University, Baoding 071002, China
| | - Hai-Tao Liu
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Ping Zhang
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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5
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Gao Y, Jennifer G A, Varathan E, Schreckenbach G. Understanding the Coordination Chemistry of Am III/Cm III in the DOTA Cavity: Insights from Energetics and Electronic Structure Theory. Inorg Chem 2023; 62:3229-3237. [PMID: 36748113 DOI: 10.1021/acs.inorgchem.2c04235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The minor actinides Am/Cm show multiple possibilities for coordination, providing great opportunities for their extraction and adsorption separation. Herein, we report complexation in an aqueous medium of AmIII/CmIII in the DOTA (H4DOTA = 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) cavity with axial ligands (OH-, F-, and H2O), based on the energetics and electronic structure properties using density functional theory (DFT). The formation and substitution reactions of OH--capped complexes are more likely to occur due to their enhanced hydration Gibbs free energies, followed by F-, and then H2O. Both the longer An-ODOTA bond lengths and the larger bite angle (∠O-An-O) in the OH--capped complexes reflect the enhanced coordination provided by the axial ligand, slightly less so for F-. Energy decomposition analysis based on the electronic structure supports the preference for OH--capped complexes with a near-perfect balance between attractive and repulsive contributions toward the interaction. Furthermore, molecular orbital analysis revealed that the frontier molecular orbitals of Am and Cm complexes are substantially different; that is, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) compositions of the Am complexes are all contributed by 5f, while the HOMO and LUMO compositions of the Cm complexes are derived from 5f and 6d, respectively. Finally, the metal-exchange reactions demonstrate competitive complexation of DOTA toward AmIII over CmIII for the OH--capped system. These results imply the importance of coordination chemistry in actinide chemistry in general and specifically in AmIII/CmIII solution chemistry.
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Affiliation(s)
- Yang Gao
- Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China.,National Health Commission Key Laboratory of Nuclear Technology Medical Transformation, Mianyang Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Mianyang 621000, China.,Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Abigail Jennifer G
- Department of Chemistry, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603203, Tamil Nadu, India
| | - Elumalai Varathan
- Department of Chemistry, Faculty of Engineering and Technology, SRM Institute of Science and Technology, Kattankulathur 603203, Tamil Nadu, India
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
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6
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Hu SX, You XX, Zou WL, Lu E, Gao X, Zhang P. Electronic Structures and Unusual Chemical Bonding in Actinyl Peroxide Dimers [An 2O 6] 2+ and [(An 2O 6)(12-crown-4 ether) 2] 2+ (An = U, Np, and Pu). Inorg Chem 2022; 61:15589-15599. [DOI: 10.1021/acs.inorgchem.2c02399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shu-Xian Hu
- Department of Physics, University of Science and Technology Beijing, Beijing 100083, China
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Xiao-Xia You
- Department of Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Wen-Li Zou
- Institute of Modern Physics, Northwest University, Xi’an, 710127, China
| | - Erli Lu
- School of Natural and Environmental Sciences, Newcastle University, Newcastle NE1 7RU, United Kingdom
| | - Xiang Gao
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Ping Zhang
- Beijing Computational Science Research Center, Beijing 100193, China
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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7
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8
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Zhang WJ, Wang C, Wang K, Zhang P, Hu SX. The stability and chemical bonding of a series tridentate ligand-actinyl complexes: [AnO2(L)2]2+ (An: U and Am). J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Jennifer G A, Gao Y, Schreckenbach G, Varathan E. Chemical bonding in actinyl(V/VI) dipyriamethyrin complexes for the actinide series from americium to californium: a computational investigation. Dalton Trans 2022; 51:10006-10019. [PMID: 35703365 DOI: 10.1039/d2dt01142e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The separation of minor actinides in their dioxocation (i.e., actinyl) form in high-valence oxidation states requires efficient ligands for their complexation. In this work, we evaluate the complexation properties of actinyls including americyl, curyl, berkelyl, and californyl in their pentavalent and hexavalent oxidation states with the dipyriamethyrin ligand (L) using density functional theory calculations. The calculated bond parameters show shorter AnOyl bonds with covalent character and longer An-N bonds with ionic character. The bonding between the actinyl cation and the ligand anion shows a flow of charges from the ligand to actinyl in all [AnV/VIO2-L]1-/0 complexes. However, across the series, backdonation of charges from the metal to the ligand becomes prominent and stabilizes the complexes. The thermodynamic parameters in the gas phase and solution suggest that the complex formation reaction is spontaneous for [CfV/VIO2-L]1-/0 complexes and spontaneous at elevated temperatures (>298.15 K) for all other complexes. Spin-orbit corrections have a quantitative impact while the overall trend remains the same. Energy decomposition analysis (EDA) reveals that the interaction between actinyl and the ligand is mainly due to electrostatic contributions that decrease from Am to Cf along with an increase in orbital contributions due to the backdonation of charges from the actinyl metal center to the ligand that greatly stabilizes the Cf complex. The repulsive Pauli energy contribution is observed to increase in the case of [AnVO2-L]1- complexes from Am to Cf while a decrease is observed among [AnVIO2-L]0 complexes, showing minimum repulsion in [CfVIO2-L]0 complex formation. Overall, the hexavalent actinyl complexes show greater stability (increasing from Am to Cf) than their pentavalent counterparts.
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Affiliation(s)
- Abigail Jennifer G
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur, Chennai 603203, Tamil Nadu, India.
| | - Yang Gao
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada. .,Institut National de La Recherche Scientifique (INRS)-Centre Énergie Matériaux Télécommunications, Varennes, QC, J3X 1P7, Canada.,Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
| | - Georg Schreckenbach
- Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - Elumalai Varathan
- Department of Chemistry, SRM Institute of Science and Technology, Kattankulathur, Chennai 603203, Tamil Nadu, India.
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10
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Gray NAG, Price JS, Emslie DJH. Uranium(IV) Thio- and Selenoether Complexes: Syntheses, Structures, and Computational Investigation of U-ER 2 Interactions. Chemistry 2021; 28:e202103580. [PMID: 34875126 DOI: 10.1002/chem.202103580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Indexed: 11/07/2022]
Abstract
Rigid thioether- and selenoether-containing pincer proligands H[AS2 Ph 2 ] (1) and H[ASe2 Ph 2 ] (2) were synthesized, and deprotonation provided the potassium salts [K(AS2 Ph 2 )(dme)] (3) and [K(ASe2 Ph 2 )(dme)2 ] (4). Reaction of two equivalents of 3 or 4 with [UI4 (dioxane)2 ] afforded the uranium thioether complex [(AS2 Ph 2 )2 UI2 ] (5) and the first example of a uranium-selenoether complex, [(ASe2 Ph 2 )2 UI2 ] (6). X-ray structures revealed distorted square antiprismatic geometries in which the AE2 Ph 2 ligands are κ3 -coordinated. The nature of the U-ER2 bonding in 5 and 6, as well as methyl-free analogues of 5 and 6 and a hypothetical ether analogue, was investigated computationally (including NBO, AIM, and ELF calculations) illustrating increasing covalency from O to S to Se.
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Affiliation(s)
- Novan A G Gray
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1, Canada
| | - Jeffrey S Price
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1, Canada
| | - David J H Emslie
- Department of Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4M1, Canada
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11
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Zhang P, Zou W, Zhang P, Hu S. Electronic Structures and Properties of Actinide‐Bimetal Compounds An
2
O
2
(An=Th to Cf) and U
2
E
2
(E=N, F, S). Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100444] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Peng Zhang
- School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China
| | - Wen‐Li Zou
- Institute of Modern Physics Northwest University Xi'an 710127 China
| | - Ping Zhang
- Institute of Applied Physics and Computational Mathematics Haidian Beijing 100088 China
| | - Shu‐Xian Hu
- School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China
- Beijing Computational Science Research Center Haidian Beijing 100193 China
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12
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Li P, Wei H, Duan M, Wu J, Li Y, Liu W, Fu Y, Xie F, Wu Y, Ma J. Actinyl-Carboxylate Complexes [AnO 2(COOH) n (H 2O) m ] 2-n (An = U, Np, Pu, and Am; n = 1-3; m = 0, 2, 4; 2 n + m = 6): Electronic Structures, Interaction Features, and the Potential to Adsorbents toward Cs Ion. ACS OMEGA 2020; 5:31974-31983. [PMID: 33344852 PMCID: PMC7745421 DOI: 10.1021/acsomega.0c04887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/23/2020] [Indexed: 06/12/2023]
Abstract
Organic compounds of actinyls and their bonding features have attracted extensive attention in nuclear waste separation due to their characteristics of separating fission products. Herein, detailed studies on the binding sites of [AnO2(COOH) n (H2O) m ]2-n (An = U, Np, Pu, and Am; n = 1-3; m = 0, 2, 4; 2n + m = 6) complexes toward Cs are predicted by calculation, and their electronic excitation characteristics were illustrated, providing theoretical supports for the design of Cs adsorbents. The quantum theory of atom in molecules and electron localization function have been implemented to analyze the chemical bonding characterization. The covalent character of An-OC bonds become weaker with increasing COOH- ligands, and the covalent interaction in An-OC bonds is more obvious than that in An-OH bonds. Total and partial population density of state suggest that the 2p orbits of O have more significant contribution in the low-energy region atoms and the 6d/5f orbits of An have more significant contribution in the high-energy region. The Cs+ best adsorption site on [UO2(COOH)2(H2O)2] and [UO2(COOH)3]- is the adjacent oxalates, and the [UO2(COOH)3]- complexes have better adsorption capacity. Besides, the electronic excitation characteristics of Cs+ adsorption on the UO2(COOH)2(H2O)2 complex were analyzed by the UV-vis spectrum and hole-electron distribution.
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Affiliation(s)
- Peng Li
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
| | - Hao Wei
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
| | - Meigang Duan
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
| | - Jizhou Wu
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
| | - Yuqing Li
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
| | - Wenliang Liu
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
| | - Yongming Fu
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
| | - Feng Xie
- Collaborative
Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory
of Advanced Reactor Engineering and Safety of Ministry of Education,
Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
| | - Yong Wu
- Institute
of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Jie Ma
- School
of Physics and Electronics Engineering, State Key Laboratory of Quantum
Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative
Innovation Center of Extreme Optics, Shanxi
University, Taiyuan 030006, China
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13
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Wang Z, Zhang Y, Liu J, Song L, Wang X, Yang X, Xu C, Li J, Ding S. From "S" to "O": experimental and theoretical insights into the atmospheric degradation mechanism of dithiophosphinic acids. RSC Adv 2020; 10:40035-40042. [PMID: 35520876 PMCID: PMC9057479 DOI: 10.1039/d0ra08841b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 10/23/2020] [Indexed: 11/21/2022] Open
Abstract
Dithiophosphinic acids (DPAHs, expressed as R1R2PSSH) are a type of sulfur-donor ligand that have been vastly applied in hydrometallurgy. In particular, DPAHs have shown great potential in highly efficient trivalent actinide/lanthanide separation, which is one of the most challenging tasks in separation science and is of great importance for the development of an advanced fuel cycle in nuclear industry. However, DPAHs have been found liable to undergo oxidative degradation in the air, leading to significant reduction in the selectivity of actinide/lanthanide separation. In this work, the atmospheric degradation of five representative DPAH ligands was investigated for the first time over a sufficiently long period (180 days). The oxidative degradation process of DPAHs elucidated by ESI-MS, 31P NMR, and FT-IR analyses is R1R2PSSH → R1R2PSOH → R1R2POOH → R1R2POO-OOPR1R2, R1R2PSSH → R1R2PSS-SSPR1R2, and R1R2PSSH → R1R2PSOH → R1R2POS-SOPR1R2. Meanwhile, the determination of pK a values through pH titration and oxidation product by PXRD further confirms the S → O transformation in the process of DPAH deterioration. DFT calculations suggest that the hydroxyl radical plays the dominant role in the oxidation process of DPAHs and the order in which the oxidation products formed is closely related to the reaction energy barrier. Moreover, nickel salts of DPAHs have shown much higher chemical stability than DPAHs, which was also elaborated through molecular orbital (MO) and adaptive natural density portioning (AdNDP) analyses. This work unambiguously reveals the atmospheric degradation mechanism of DPAHs through both experimental and theoretical approaches. At the application level, the results not only provide an effective way to preserve DPAHs but could also guide the design of more stable sulfur-donor ligands in the future.
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Affiliation(s)
- Zhipeng Wang
- College of Chemistry, Sichuan University Chengdu 610064 China
| | - Yixiang Zhang
- Department of Chemistry, Key Laboratory of Organic Optoelectronics, Molecular Engineering of the Ministry of Education, Tsinghua University Beijing 100084 China
| | - Jingjing Liu
- Department of Chemistry, Key Laboratory of Organic Optoelectronics, Molecular Engineering of the Ministry of Education, Tsinghua University Beijing 100084 China
| | - Lianjun Song
- College of Chemistry, Sichuan University Chengdu 610064 China
| | - Xueyu Wang
- College of Chemistry, Sichuan University Chengdu 610064 China
| | - Xiuying Yang
- College of Chemistry, Sichuan University Chengdu 610064 China
| | - Chao Xu
- Collaborative Innovation Center of Advanced Nuclear Energy Technology, Institute of Nuclear and New Energy Technology, Tsinghua University Beijing 100084 China
| | - Jun Li
- Department of Chemistry, Key Laboratory of Organic Optoelectronics, Molecular Engineering of the Ministry of Education, Tsinghua University Beijing 100084 China
| | - Songdong Ding
- College of Chemistry, Sichuan University Chengdu 610064 China
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14
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Zhang P, Liu H, Zou W, Zhang P, Hu SX. Relativistic Effects Stabilize the Planar Wheel-like Structure of Actinide-Doped Gold Clusters: An@Au 7 (An = Th to Cm). J Phys Chem A 2020; 124:8173-8183. [PMID: 32845148 DOI: 10.1021/acs.jpca.0c02148] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Despite the chemistry of actinide-ligand bonding is continuing and of burgeoning interest, investigations of the chemical bonding of bimetallic complexes involving transuranics remain relatively less, and there are rarely studies on the bonding features between actinide and coinage metals (CM). We present a systematic research on the series of An@Au7 (An = Th to Cm), UCM7 (CM = Cu, Ag, Au), and WAu7 clusters to investigate the unique geometries, electronic structures, and chemical bonding between An 5f6d orbitals and CM ns orbitals, and to find their periodicity across the actinides and within the group of transition metals. A unique planar wheel-like structure for An@Au7 clusters with the help of actinide metals encapsulation via spin-orbit coupling, resulting in An(III). Instead, the transition-metal (TM) element W retains its usual six-gold-coordination structure in WAu7, thus forcing the seventh Au out of plane. The An-CM interactions, depending on the ion radii, become stronger with the increase of the atomic number of the actinide metals, as well as the CM. These results show that the presence of actinides in clusters can lead to unique electronic and geometrical structures.
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Affiliation(s)
- Peng Zhang
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Haitao Liu
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Wenli Zou
- Institute of Modern Physics, Northwest University and Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an 710127, China
| | - Ping Zhang
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China
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Zhang P, Wang YX, Zhang P, Wang SA, Hu SX. Evaluation of Chemical Bonding in Actinyl(VI/V) Oxo-Crown-Ether Complexes for Actinide Series from Uranium to Curium. Inorg Chem 2020; 59:11953-11961. [PMID: 32806007 DOI: 10.1021/acs.inorgchem.0c00535] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The separation and management of nuclear waste is one of the problems that needs to be solved urgently, so finding a new radiation-proof and durable extractant to deal with nuclear waste is a difficult but desirable task. Since the successful isolation of the first pentavalent plutonium crown ether complex recently (Wang et al. CCS Chem. 2020, 2, 425-431), complexes with actinyl(V/VI) inserted into the cavity of 18-crown-6 ether (oxo-18C6), as well as their bonding character, need to be explored. Here we present a series of novel crown ether complexes containing actinyl(V/VI) and oxo-18C6 via computational prediction and analysis. On the basis of the calculations, actinyl(V/VI) are thermodynamically feasible and can be stabilized by oxo-18C6 ligand via six dative bonds between An ions and the oxo-18C6 O atoms in the "insertion" structure of [AnO2(18C6)]2+/+ complexes. The stability of actinyl(VI) species generally falls at minor actinides, ascribed to the reduced highest possible oxidation states of curium, which is mainly attributed to the mixing of bonding orbitals and non-bonding orbitals as well as the increase of occupation on partially 5f antibonding orbitals. It is found that the interactions between the actinyl(V/VI) and oxo-18C6 are mainly electronic interactions, with the well-known covalency contributions generally decreasing from uranium to curium due to energy degeneracy and spatial orbital contraction. This work would give a basic understanding of the coordination chemistry of actinyl(V/VI), which also provides inspirations on the design of new extractants for actinide separations.
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Affiliation(s)
- Peng Zhang
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Ya-Xing Wang
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, China
| | - Ping Zhang
- Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Shu-Ao Wang
- State Key Laboratory of Radiation Medicine and Protection, School for Radiological and Interdisciplinary Sciences (RAD-X) and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, Soochow University, Suzhou 215123, China
| | - Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China
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Hu SX, Zhang P, Zou W, Zhang P. New theoretical insights into high-coordination-number complexes in actinides-centered borane. NANOSCALE 2020; 12:15054-15065. [PMID: 32400819 DOI: 10.1039/d0nr01955k] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The coordination number of a given element affects its behavior, and consequently, there is great interest in understanding the related chemistry, which could greatly promote the extension and development of new materials, but remains challenging. Herein, we report a new record high coordination number (CN) for actinides established in the cage-like An(BH)24 (An = Th to Cm) via using relativistic quantum chemistry methods. Analysis of U(BH)n (n = 1 to 24) confirmed these series of systems as being geometric minima, with the BH acting as a ligand located in the first shell around the uranium. In contrast, global searches revealed a low CN half-cage structure for UB24, which could be extended to the series of AnB24 materials and which prevails over the competing structural isomers, such as cages. The intrinsic geometric difference for AnB24 and An(BH)24 mainly arise from the B sp3 hybridization in borane inducing strong interactions between An 5f6d7s hybrid orbitals and B 2pz orbitals in An(BH)24 compared to that of AnB24. This fundamental trend presents a valuable insight for future experimental endeavors searching for isolable complexes with high-coordination actinide and provides details of a new structural motif of boron clusters and nanostructures.
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Affiliation(s)
- Shu-Xian Hu
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China and Beijing Computational Science Research Center, Beijing 100193, China. and Institute of Modern Physics, Northwest University, and Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an, 710127, China
| | - Peng Zhang
- Beijing Computational Science Research Center, Beijing 100193, China.
| | - Wenli Zou
- Institute of Modern Physics, Northwest University, and Shaanxi Key Laboratory for Theoretical Physics Frontiers, Xi'an, 710127, China
| | - Ping Zhang
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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Hu SX, Qin J, Zhang P, Shuai MB, Zhang P. Theoretical Insight into Coordination Chemistry of Am(VI) and Am(V) with Phenanthroline Ligand: Implications for High Oxidation State Based Minor Actinide Separation. Inorg Chem 2020; 59:6338-6350. [PMID: 32286060 DOI: 10.1021/acs.inorgchem.0c00452] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Despite continuing and burgeoning interest in americium (Am) coordination chemistry in recent years, investigations of the electronic structures and bonding chemistry of high oxidation state americium complexes and their implications for minor actinide separation remain relatively less explored to date. Here, we used density functional theory (DFT) to create high oxidation states of americium but experimentally feasible models of Am(V) and Am(VI) complexes of phenanthroline ligand (DAPhen) as [AmO2(L)]1+/2+ and [AmO3(L)]1+ (L = 2,9-bis[(N,N-dimethyl)-carbonyl]-1,10-phenanthroline (oxo-DAPhen, LO) and 2,9-bis[(N,N-dimethyl)-thio-carbonyl]-1,10-phenanthroline (thio-DAPhen, LS)), meanwhile comparing these with [UO2(L)]2+. On the basis of the calculations, the Am(V) and Am(VI) oxidation state are thermodynamically feasible and can be stabilized by DAPhen ligands. From a comparative study, the strength of thio-DAPhen in the separation of high oxidation state Am emerges better than does oxo-DAPhen, which relates to the nature, energy level, and spatial arrangement of their frontier orbitals. This study provides fundamental knowledge toward understanding the transuranic separations processes, which has implications in designing new, more selective extraction processes for the separation of Am from curium (Cm) as well as lanthanide.
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Affiliation(s)
- Shu-Xian Hu
- School of Mathematics and Physics, University of Science and Technology Beijing, Beijing 100083, China
| | - Jianwei Qin
- Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621908, China
| | - Peng Zhang
- Beijing Computational Science Research Center, Beijing 100193, China
| | - Mao-Bing Shuai
- Science and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621908, China
| | - Ping Zhang
- Laboratory of Computational Physics, Institute of Applied Physics and Computational Mathematics, Beijing 100088, China
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Hu SX, Lu E, Liddle ST. Prediction of high bond-order metal-metal multiple-bonds in heterobimetallic 3d-4f/5f complexes [TM-M{N(o-[NCH 2P(CH 3) 2]C 6H 4) 3}] (TM = Cr, Mn, Fe; M = U, Np, Pu, and Nd). Dalton Trans 2019; 48:12867-12879. [PMID: 31389454 DOI: 10.1039/c9dt03086g] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Despite continuing and burgeoning interest in f-block complexes and their bonding chemistry in recent years, investigations of the electronic structures and oxidation states of heterobimetallic complexes, and their bonding features between transition-metals (TMs) and f-elements remain relatively less explored. Here, we report a quantum chemical computational study on the series of TM-actinide and -neodymium complexes [TMAn(L)] and [TMNd(L)] [An = U, Np, Pu; TM = Cr, Mn, Fe; L = {N(o-[NCH2P(CH3)2]C6H4)3}3-] in order to explore periodic trend, generalities and differences in the electronic structure and metal-metal bonding between f-block and d-block elements. Based on the calculations, we find up to five-fold covalent multiple bonding between actinide and transition metal ions, which is in sharp contrast with a single bond between neodymium and transition metals. From a comparative study, a general trend of strength of the An-TM interaction emerges in accordance with the atomic number of the actinide metal, which relates to the nature, energy level, and spatial arrangement of their frontier orbitals. The trend presents a valuable insight for future experimental endeavour searching for isolable complexes with strong and multiple An-TM bonding interactions, especially for the experimentally challenging transuranic elements that require targeted research due to their radioactive nature.
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Affiliation(s)
- Shu-Xian Hu
- Department of Physics, University of Science and Technology Beijing, Beijing 100083, China. and Beijing Computational Science Research Center, Beijing 100193, China
| | - Erli Lu
- School of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Stephen T Liddle
- School of Chemistry and Centre for Radiochemistry Research, The University of Manchester, Oxford Road, Manchester M13 9PL, UK
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Hu SX, Jian J, Li J, Gibson JK. Destruction of the Uranyl Moiety in a U(V) “Cation–Cation” Interaction. Inorg Chem 2019; 58:10148-10159. [DOI: 10.1021/acs.inorgchem.9b01265] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Jiwen Jian
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Jun Li
- Department of Chemistry and Key Laboratory of Organic Optoelectronics & Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
| | - John K. Gibson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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Duan M, Li P, Zhao H, Xie F, Ma J. Organic Compounds of Actinyls: Systematic Computational Assessment of Structural and Topological Properties in [AnO 2(C 2O 4) n] (2 n-2)- (An = U, Np, Pu, Am; n = 1-3) Complexes. Inorg Chem 2019; 58:3425-3434. [PMID: 30785280 DOI: 10.1021/acs.inorgchem.8b03538] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Exploring the bonding features between organics and actinide elements is a fundamental topic in nuclear waste separation. In this work, [AnO2(C2O4) n](2 n-2)- (An = U, Np, Pu, and Am; n = 1-3) complexes have been characterized by density functional theory. The actinyl oxalate complexes are found to exhibit the typical An-Oyl, An-Oeq bonds and Oyl-An-Oyl angles. Interatomic interaction analyzed by electron density difference, charge decomposition analysis, charges population, bond order, electron localization function, and quantum theory of atom in molecules indicates that An-Oeq bonds are ionic (closed-shell) bonding interaction with a small degree of covalent character. The similarities and differences between isomers have been discussed in the actinide coordination chemistry, and the orbital interactions also have been investigated through total, partial, and overlap population density of state diagrams. Besides, the electrostatic potential was used to predict the adsorption sites on the molecular vdW surface.
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Affiliation(s)
- Meigang Duan
- Laser Spectroscopy Laboratory, School of Physics and Electronics Engineering, Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan 030006 , China
| | - Peng Li
- Laser Spectroscopy Laboratory, School of Physics and Electronics Engineering, Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan 030006 , China
| | - Huifeng Zhao
- Laser Spectroscopy Laboratory, School of Physics and Electronics Engineering, Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan 030006 , China
| | - Feng Xie
- Institute of Nuclear and New Energy Technology, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education , Tsinghua University , Beijing 100084 , China
| | - Jie Ma
- Laser Spectroscopy Laboratory, School of Physics and Electronics Engineering, Collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan 030006 , China
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Hu SX, Liu HT, Liu JJ, Zhang P, Ao B. Electronic Structure and Chemical Bonding of [AmO 2(H 2O) n ] 2+/1. ACS OMEGA 2018; 3:13902-13912. [PMID: 31458086 PMCID: PMC6644428 DOI: 10.1021/acsomega.8b01324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 09/20/2018] [Indexed: 06/10/2023]
Abstract
Systematic americyl-hydration cations were investigated theoretically to understand the electronic structures and bonding in [(AmO2)(H2O) n ]2+/1+ (n = 1-6). We obtained the binding energy using density functional theory methods with scalar relativistic and spin-orbit coupling effects. The geometric structures of these species have been investigated in aqueous solution via an implicit solvation model. Computational results reveal that the complexes of five equatorial water molecules coordinated to americyl ions are the most stable due to the enhanced ionic interactions between the AmO2 2+/1+ cation and multiple oxygen atoms as electron donors. As expected, Am-Owater bonds in such series are electrostatic in nature and contain a generally decreasing covalent character when hydration number increases.
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Affiliation(s)
- Shu-Xian Hu
- Beijing
Computational Science Research Center, Beijing 100193, China
| | - Hai-Tao Liu
- Institute
of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Jing-Jing Liu
- Beijing
Computational Science Research Center, Beijing 100193, China
| | - Ping Zhang
- Institute
of Applied Physics and Computational Mathematics, Beijing 100088, China
| | - Bingyun Ao
- Science
and Technology on Surface Physics and Chemistry Laboratory, Mianyang 621908, China
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Hu SX, Chen M, Ao B. Theoretical studies on the oxidation states and electronic structures of actinide-borides: AnB 12 (An = Th-Cm) clusters. Phys Chem Chem Phys 2018; 20:23856-23863. [PMID: 29999053 DOI: 10.1039/c8cp02561d] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
As B12 clusters exhibit significant structural stability due to double aromaticity, metal doped-B12 clusters often prefer a half sandwich structure. Herein, we report a systematic theoretical study on the geometric and electronic structures, and chemical bonding of the half sandwich AnB12 (An = Th to Cm) clusters to explore the stability and extent of covalency of the An-B bonds of these actinide borides. We have shown that in the gas-phase clusters, the significant stability of AnB12 is determined by electrostatic and orbital interactions between the An 5f6d7s orbitals and π-type molecular orbitals from B 2p orbitals of the B12 unit. A change-over of An-B bond length from An = Th to Cm is found at An = Pa as a result of actinide contraction combined with weakening An-B bonding due to an energy decrease and orbital localization of the 5f orbitals. Consistently, the oxidation states of the An atoms at first increase from Th(f0)IV to Pa(f0)V, and then due to the 5f-AO contraction, they smoothly decline to U(f2)IV, Np(f4)III and Pu(f5)III, and then eventually to Am(f7)II but Cm(f7)III, both with a half-filled 5f shell.
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Affiliation(s)
- Shu-Xian Hu
- Beijing Computational Science Research Center, Beijing 100193, China.
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