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NAGAME Y, SATO TK. Chemical characterization of heavy actinides and light transactinides - Experimental achievements at JAEA. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2024; 100:165-189. [PMID: 38462500 PMCID: PMC11105975 DOI: 10.2183/pjab.100.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 11/17/2023] [Indexed: 03/12/2024]
Abstract
The chemical characterization of the heaviest elements at the farthest reach of the periodic table (PT) and the classification of these elements in the PT are undoubtedly crucial and challenging subjects in chemical and physical sciences. The elucidation of the influence of relativistic effects on their outermost electronic configuration is also a critical and fascinating aspect. However, the heaviest elements with atomic numbers Z ≳ 100 must be produced at accelerators using nuclear reactions of heavy ions and target materials. Therefore, production rates for these elements are low, and their half-lives are as short as a few seconds to a few minutes; they are usually available in a quantity of only a few atoms at a time. Here, we review some highlighted studies on heavy actinide and light transactinide chemical characterization performed at the Japan Atomic Energy Agency tandem accelerator facility. We discuss briefly the prospects for future studies of the heaviest elements.
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Affiliation(s)
- Yuichiro NAGAME
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Naka-gun, Ibaraki 319-1195, Japan
| | - Tetsuya K. SATO
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai, Naka-gun, Ibaraki 319-1195, Japan
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2
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Abramov PA, Sokolov MN. Not So Similar: Different Ways of Nb(V) and Ta(V) Catecholate Complexation. Molecules 2023; 28:4912. [PMID: 37446574 PMCID: PMC10361208 DOI: 10.3390/molecules28134912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 07/15/2023] Open
Abstract
The reactions between catechol (H2cat) and niobium(V) or tantalum(V) precursors in basic aqueous solutions lead to the formation of catecholate complexes of different natures. The following complexes were isolated and characterized by single-crystal X-ray diffraction (SCXRD): (1) (NH4)3[NbO(cat)3]∙4H2O; (2) K2[Nb(cat)3(Hcat)]·2H2cat·2H2O; (3) Cs3[NbO(cat)3]·H2O; (4) (NH4)4[Ta2O(cat)6]·3H2O; (5) Cs2[Ta(cat)3(Hcat)]·H2cat; (6) Cs4[Ta2O(cat)6]·7H2O. The isolated crystalline products were characterized by elemental analysis, X-ray powder diffraction (XRPD), FTIR, and TGA. The structural features of these complexes, such as {Ta2O} unit geometry, Cs-π interactions, and crystal packing effects, are discussed.
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Affiliation(s)
- Pavel A Abramov
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., 630090 Novosibirsk, Russia
- Research School of Chemistry and Applied Biomedical Sciences, Tomsk Polytechnic University, 634034 Tomsk, Russia
| | - Maxim N Sokolov
- Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Akad. Lavrentiev Ave., 630090 Novosibirsk, Russia
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3
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Pinheiro AS, Gargano R, Santos PHGD, de Macedo LGM. Fully relativistic study of polyatomic closed shell E121X 3 (X = F, Cl, Br) molecules: effects of Gaunt interaction, relativistic effects and advantages of an exact-two component (X2C) hamiltonian. J Mol Model 2021; 27:262. [PMID: 34435260 DOI: 10.1007/s00894-021-04861-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Accepted: 07/29/2021] [Indexed: 10/20/2022]
Abstract
In this study, all electron relativistic calculations with 4-component Dirac-Coulomb-Breit (DCB), 4-component Dirac-Coulomb (DC), Dyall's spin-free Dirac-Coulomb (SFDC), exact two-component (X2C) and Levy-Leblond non-relativistic hamiltonians calculations were performed in polyatomic closed shell E121X3 (X = F, Cl, Br) within density functional theory (DFT) with hybrid functional B3LYP, where E121 is the superheavy element (SHE) with Z = 121. The aims of this study were to investigate relativistic effects in polyatomic E121X3 (X = F, Cl, Br) and verify the importance of Gaunt effects. The results demonstrate that although the effect of Gaunt interaction is small on change equilibrium bond lengths and bonding, it is important to obtain reliable vibrational frequencies. Moreover, it is possible to use the X2C spin-free hamiltonian to lower computational costs in a fully relativistic investigation of polyatomics including the SHE of the 8th period. Finally, a comparison between electron localization function (ELF) analysis and Mulliken population analysis suggests bonding similarity between LaBr3 and E121Br3. Graphical Abstract Relativistic 4-Component calculations suggest bond similarity between LaBr3 and E121Br3.
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Affiliation(s)
- Alan Sena Pinheiro
- Programa de Pós-Graduação em Química/PPGQ, Instituto de Ciências Exatas e Naturais (ICEN), Universidade Federal Do Pará (UFPA), Belém, PA, 66075-110, Brazil
| | - Ricardo Gargano
- Instituto de Física, Universidade de Brasília (UnB), P.O. Box 04455, Brasília, DF, 70919-970, Brazil
| | - Paulo Henrique Gomes Dos Santos
- Campus Centro Oeste Dona Lindu (CCO/UFSJ) Divinópolis, Universidade Federal de São João del Rei, São João del Rei, MG, 35501-296, Brazil
| | - Luiz Guilherme Machado de Macedo
- Campus Centro Oeste Dona Lindu (CCO/UFSJ) Divinópolis, Universidade Federal de São João del Rei, São João del Rei, MG, 35501-296, Brazil.
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4
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Ferrier MG, Kmak KN, Kerlin WM, Valdez CA, Despotopulos JD. Transactinide studies with sulfur macrocyclic extractant using mercury. J Radioanal Nucl Chem 2020. [DOI: 10.1007/s10967-020-07320-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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5
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Visentin G, Laatiaoui M, Viehland LA, Buchachenko AA. Mobility of the Singly-Charged Lanthanide and Actinide Cations: Trends and Perspectives. Front Chem 2020; 8:438. [PMID: 32528933 PMCID: PMC7262671 DOI: 10.3389/fchem.2020.00438] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 04/27/2020] [Indexed: 11/13/2022] Open
Abstract
The current status of gaseous transport studies of the singly-charged lanthanide and actinide ions is reviewed in light of potential applications to superheavy ions. The measurements and calculations for the mobility of lanthanide ions in He and Ar agree well, and they are remarkably sensitive to the electronic configuration of the ion, namely, whether the outer electronic shells are 6s, 5d6s or 6s2. The previous theoretical work is extended here to ions of the actinide family with zero electron orbital momentum: Ac+ (7s2, 1S), Am+ (5f77s 9S°), Cm+ (5f77s2 8S°), No+ (5f147s 2S), and Lr+ (5f147s2 1S). The calculations reveal large systematic differences in the mobilities of the 7s and 7s2 groups of ions and other similarities with their lanthanide analogs. The correlation of ion-neutral interaction potentials and mobility variations with spatial parameters of the electron distributions in the bare ions is explored through the ionic radii concept. While the qualitative trends found for interaction potentials and mobilities render them appealing for superheavy ion research, lack of experimental data and limitations of the scalar relativistic ab initio approaches in use make further efforts necessary to bring the transport measurements into the inventory of techniques operating in "one atom at a time" mode.
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Affiliation(s)
- Giorgio Visentin
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Mustapha Laatiaoui
- Department Chemie, Johannes Gutenberg-Universität, Mainz, Germany.,Helmholtz-Institut Mainz, Mainz, Germany
| | - Larry A Viehland
- Science Department, Chatham University, Pittsburgh, PA, United States
| | - Alexei A Buchachenko
- Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow, Russia.,Theoretical Department, Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka, Russia
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6
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Pershina V. Relativity in the electronic structure of the heaviest elements and its influence on periodicities in properties. RADIOCHIM ACTA 2019. [DOI: 10.1515/ract-2018-3098] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Theoretical chemical studies demonstrated crucial importance of relativistic effects in the physics and chemistry of superheavy elements (SHEs). Performed, with many of them, in a close link to the experimental research, those investigations have shown that relativistic effects determine periodicities in physical and chemical properties of the elements in the chemical groups and rows of the Periodic Table beyond the 6th one. They could, however, also lead to some deviations from the established trends, so that the predictive power of the Periodic Table in this area may be lost. Results of those studies are overviewed here, with comparison to the recent experimental investigations.
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Affiliation(s)
- Valeria Pershina
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstr. 1 , D-64291 Darmstadt , Germany
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7
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Abstract
Abstract
The fundamental principles of the periodic table guide the research and development of the challenging experiments with transactinide elements. This guidance is elucidated together with experimental results from gas phase chemical studies of the transactinide elements with the atomic numbers 104–108 and 112–114. Some deduced chemical properties of these superheavy elements are presented here in conjunction with trends established by the periodic table. Finally, prospects are presented for further chemical investigations of transactinides based on trends in the periodic table.
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Affiliation(s)
- Robert Eichler
- Laboratory of Radiochemistry, Paul Scherrer Institute , Forschungsstrasse 111 , 5232 Villigen PSI , Switzerland
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Chiera NM, Sato TK, Tomitsuka T, Asai M, Suzuki H, Tokoi K, Toyoshima A, Tsukada K, Nagame Y. Formation and thermochemical properties of oxychlorides of niobium (Nb) and tantalum (Ta): Towards the gas-phase investigation of dubnium (Db) oxychloride. Inorganica Chim Acta 2019. [DOI: 10.1016/j.ica.2018.10.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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9
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Yokoyama A, Kitayama Y, Fukuda Y, Kikunaga H, Murakami M, Komori Y, Yano S, Haba H, Tsukada K, Toyoshima A. Extraction behavior of rutherfordium as a cationic fluoride complex with a TTA chelate extractant from HF/HNO3 acidic solutions. RADIOCHIM ACTA 2018. [DOI: 10.1515/ract-2018-2949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The aim of this study was to identify relevant Rf chemical species by using reversed-phase extraction chromatography with 2-thenoyltrifluoroacetone (TTA) resin as the stationary phase. Because TTA can be used to extract specific metal ions, the distribution ratios of the system enabled determination of the specific complex formation constant of Rf. We performed several experiments on chemical systems with Zr, Hf, No, and Rf, determined their adsorption coefficients, and deduced the K
d values for Rf.
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Affiliation(s)
- Akihiko Yokoyama
- Institute of Science and Engineering, Kanazawa University , Kanazawa, Ishikawa 920-1192 , Japan
| | - Yuta Kitayama
- Graduate School of Natural Science and Technology, Kanazawa University , Kanazawa, Ishikawa 920-1192 , Japan
| | - Yoshiki Fukuda
- Graduate School of Natural Science and Technology, Kanazawa University , Kanazawa, Ishikawa 920-1192 , Japan
| | - Hidetoshi Kikunaga
- Research Center for Electron Photon Science, Tohoku University , Sendai, Miyagi 982-0826 , Japan
| | - Masashi Murakami
- Nishina Center for Accelerator-Based Science, RIKEN, Wako , Saitama 351-0198 , Japan
| | - Yukiko Komori
- Nishina Center for Accelerator-Based Science, RIKEN, Wako , Saitama 351-0198 , Japan
| | - Shinya Yano
- Nishina Center for Accelerator-Based Science, RIKEN, Wako , Saitama 351-0198 , Japan
| | - Hiromitsu Haba
- Nishina Center for Accelerator-Based Science, RIKEN, Wako , Saitama 351-0198 , Japan
| | - Kazuaki Tsukada
- Advanced Science Research Center, Japan Atomic Energy Agency , Tokai, Ibaraki 319-1195 , Japan
| | - Atsushi Toyoshima
- Advanced Science Research Center, Japan Atomic Energy Agency , Tokai, Ibaraki 319-1195 , Japan
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10
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Vinoth P, Sankar P. Encoding of coordination complexes with XML. J Mol Graph Model 2017; 76:242-259. [PMID: 28735171 DOI: 10.1016/j.jmgm.2017.07.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/08/2017] [Accepted: 07/10/2017] [Indexed: 11/29/2022]
Abstract
An in-silico system to encode structure, bonding and properties of coordination complexes is developed. The encoding is achieved through a semantic XML markup frame. Composition of the coordination complexes is captured in terms of central atom and ligands. Structural information of central atom is detailed in terms of electron status of valence electron orbitals. The ligands are encoded with specific reference to the electron environment of ligand centre atoms. Behaviour of ligands to form low or high spin complexes is accomplished by assigning a Ligand Centre Value to every ligand based on the electronic environment of ligand centre atom. Chemical ontologies are used for categorization purpose and to control different hybridization schemes. Complexes formed by the central atoms of transition metal, non-transition elements belonging to s-block, p-block and f-block are encoded with a generic encoding platform. Complexes of homoleptic, heteroleptic and bridged types are also covered by this encoding system. Utility of the encoded system to predict redox electron transfer reaction in the coordination complexes is demonstrated with a simple application.
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Affiliation(s)
- P Vinoth
- Department of Chemistry, Pondicherry Engineering College, Puducherry 605 014, India
| | - P Sankar
- Department of Chemistry, Pondicherry Engineering College, Puducherry 605 014, India.
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11
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Schwerdtfeger P. Toward an accurate description of solid-state properties of superheavy elements. EPJ WEB OF CONFERENCES 2016. [DOI: 10.1051/epjconf/201613107004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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12
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Despotopulos JD, Kmak KN, Gharibyan N, Henderson RA, Moody KJ, Shaughnessy DA, Sudowe R. Characterization of the homologs of flerovium with crown ether based extraction chromatography resins: studies in hydrochloric acid. J Radioanal Nucl Chem 2016. [DOI: 10.1007/s10967-016-4917-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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13
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Xu C, Xiong X, Li W, Li J. Periodicity and Covalency of [MX
2
]
–
(M = Cu, Ag, Au, Rg; X = H, Cl, CN) Complexes. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Cong‐Qiao Xu
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, P. R. China, http://www.junlilab.org/
| | - Xiao‐Gen Xiong
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, P. R. China, http://www.junlilab.org/
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, P. R. China
| | - Wan‐Lu Li
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, P. R. China, http://www.junlilab.org/
| | - Jun Li
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, P. R. China, http://www.junlilab.org/
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14
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Wang YL, Hu HS, Li WL, Wei F, Li J. Relativistic Effects Break Periodicity in Group 6 Diatomic Molecules. J Am Chem Soc 2016; 138:1126-9. [PMID: 26787134 DOI: 10.1021/jacs.5b11793] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The finding of the periodic law is a milestone in chemical science. The periodicity of light elements in the Periodic Table is fully accounted for by quantum mechanics. Here we report that relativistic effects change the bond multiplicity of the group 6 diatomic molecules M2 (M = Cr, Mo, W, Sg) from hextuple bonds for Cr2, Mo2, W2 to quadruple bonds for Sg2, thus breaking the periodicity in the nonrelativistic domain. The same trend is also found for other superheavy-element diatomics Rf2, Db2, Bh2, and Hs2.
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Affiliation(s)
- Yi-Lei Wang
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University , Beijing 100084, China
| | - Han-Shi Hu
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University , Beijing 100084, China
| | - Wan-Lu Li
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University , Beijing 100084, China
| | - Fan Wei
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University , Beijing 100084, China
| | - Jun Li
- Department of Chemistry & Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University , Beijing 100084, China
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15
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Abstract
Abstract
The chemistry of superheavy elements - or transactinides from their position in the Periodic Table - is summarized. After giving an overview over historical developments, nuclear aspects about synthesis of neutron-rich isotopes of these elements, produced in hot-fusion reactions, and their nuclear decay properties are briefly mentioned. Specific requirements to cope with the one-atom-at-a-time situation in automated chemical separations and recent developments in aqueous-phase and gas-phase chemistry are presented. Exciting, current developments, first applications, and future prospects of chemical separations behind physical recoil separators (“pre-separator”) are discussed in detail. The status of our current knowledge about the chemistry of rutherfordium (Rf, element 104), dubnium (Db, element 105), seaborgium (Sg, element 106), bohrium (Bh, element 107), hassium (Hs, element 108), copernicium (Cn, element 112), and element 114 is discussed from an experimental point of view. Recent results are emphasized and compared with empirical extrapolations and with fully-relativistic theoretical calculations, especially also under the aspect of the architecture of the Periodic Table.
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Affiliation(s)
- M. Schädel
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan / GSI Helmholtz Center for Heavy Ion Research, 64291 Darmstadt, Germany
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16
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17
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Heavy element chemistry facilities at Texas A&M University. J Radioanal Nucl Chem 2014. [DOI: 10.1007/s10967-013-2676-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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18
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Toyoshima A, Li Z, Asai M, Sato N, Sato TK, Kikuchi T, Kaneya Y, Kitatsuji Y, Tsukada K, Nagame Y, Schädel M, Ooe K, Kasamatsu Y, Shinohara A, Haba H, Even J. Measurement of the Md3+/Md2+ reduction potential studied with flow electrolytic chromatography. Inorg Chem 2013; 52:12311-3. [PMID: 24116851 DOI: 10.1021/ic401571h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reduction behavior of mendelevium (Md) was studied using a flow electrolytic chromatography apparatus. By application of the appropriate potentials on the chromatography column, the more stable Md(3+) is reduced to Md(2+). The reduction potential of the Md(3+) + e(-) → Md(2+) couple was determined to be -0.16 ± 0.05 V versus a normal hydrogen electrode.
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19
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Borschevsky A, Pershina V, Eliav E, Kaldor U. Ab initio studies of atomic properties and experimental behavior of element 119 and its lighter homologs. J Chem Phys 2013; 138:124302. [DOI: 10.1063/1.4795433] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Türler A, Pershina V. Advances in the Production and Chemistry of the Heaviest Elements. Chem Rev 2013; 113:1237-312. [DOI: 10.1021/cr3002438] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Andreas Türler
- Laboratory
of Radiochemistry
and Environmental Chemistry, Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland
- Laboratory of Radiochemistry
and Environmental Chemistry, Department Biology and Chemistry, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Valeria Pershina
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Planckstrasse
1, D-64291 Darmstadt, Germany
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21
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Relativistic effects in bonding and isomerization energy of the superheavy roentgenium (111Rg) cyanide. Polyhedron 2012. [DOI: 10.1016/j.poly.2012.03.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Development, relevance, and applications of “atom-at-a-time” techniques. J Radioanal Nucl Chem 2012. [DOI: 10.1007/s10967-011-1361-y] [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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23
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Ishii Y, Toyoshima A, Tsukada K, Asai M, Li Z, Nagame Y, Miyashita S, Mori T, Suganuma H, Haba H, Goto SI, Kudo H, Akiyama K, Oura Y, Shinohara A, Schädel M, Pershina V, Kratz JV. Fluorido Complex Formation of Element 104, Rutherfordium (Rf). BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2011. [DOI: 10.1246/bcsj.20110126] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Abstract
Abstract
Spectacular developments in relativistic quantum theory and computational algorithms in the last two decades allowed for accurate predictions of properties of the heaviest elements and their experimental behaviour. The most recent works in this area of investigations are overviewed. Preference is given to those related to experimental research. The role of relativistic effects is elucidated.
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25
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Abstract
Abstract
The experimental techniques developed to perform rapid chemical separations of the heaviest elements in the aqueous phase are presented. In general, these include transport of the nuclear reaction products to a separation device by the gas-jet technique and dissolution in an aqueous solution containing inorganic ligands for complex formation. The complexes are chemically characterized by a partition method which can be liquid–liquid extraction, ion-exchange- or reversed-phase extraction chromatography. The separated fractions are quickly evaporated to dryness for the preparation of samples for α-particle spectroscopy. Comments are given on the special situation in which chemistry has to be studied with single atoms. Theoretical predictions of chemical properties are compared to the presently known chemical behaviour of rutherfordium, Rf (element 104), dubnium, Db (element 105), seaborgium, Sg (element 106), and hassium, Hs (element 108) and to that of their lighter homologs in the Periodic Table in order to assess the role of relativistic effects in the chemistry of the heaviest elements.
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26
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Chang Z, Li J, Dong C. Ionization Potentials, Electron Affinities, Resonance Excitation Energies, Oscillator Strengths, And Ionic Radii of Element Uus (Z = 117) and Astatine. J Phys Chem A 2010; 114:13388-94. [DOI: 10.1021/jp107411s] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Zhiwei Chang
- Key Laboratory of Atomic and Molecular Physics and Functional Material of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, 730070 Lanzhou, China
| | - Jiguang Li
- Key Laboratory of Atomic and Molecular Physics and Functional Material of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, 730070 Lanzhou, China
| | - Chenzhong Dong
- Key Laboratory of Atomic and Molecular Physics and Functional Material of Gansu Province, College of Physics and Electronic Engineering, Northwest Normal University, 730070 Lanzhou, China
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27
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Pershina V. Electronic Structure and Chemistry of the Heaviest Elements. CHALLENGES AND ADVANCES IN COMPUTATIONAL CHEMISTRY AND PHYSICS 2010. [DOI: 10.1007/978-1-4020-9975-5_11] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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28
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Pershina V, Trubert D, Le Naour C, Kratz JV. Theoretical predictions of hydrolysis and complex formation of group-4 elements Zr, Hf and Rf in HF and HCl solutions. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2002.90.12_2002.869] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
SummaryFully relativistic molecular density–functional calculations of the electronic structures of hydrated, hydrolyzed and fluoride/chloride complexes have been performed for group–4 elements Zr, Hf, and element 104, Rf. Using the electronic density distribution data, relative values of the free energy change for hydrolysis and complex formation reactions were defined. The results show the following trend for the first hydrolysis step of the cationic species: Zr > Hf > Rf in agreement with experiments. For the complex formation in HF solutions, the trend to a decrease from Zr to Hf is continued with Rf, provided no hydrolysis takes place. At pH > 0, further fluorination of hydrolyzed species or fluoro–complexes has an inversed trend in the group Rf ≥ Zr > Hf, with the difference between the elements being very small. For the complex formation in HCl solutions, the trend is continued with Rf, so that Zr > Hf > Rf independently of pH. A decisive energetic factor in hydrolysis or complex formation processes proved to be a predominant electrostatic metal–ligand interaction. Trends in theKd(distribution coefficient) values for the group–4 elements are expected to follow those of the complex formation.
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Pershina V. Predictions of adsorption behaviour of the heaviest elements in a comparative study from the electronic structure calculations. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.93.3.125.61612] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Summary
Thermodynamics of adsorption of gaseous species on the surface of a gas chromatography column is considered using the knowledge of the electronic structure of the adsorbate. Relevant equations based on a model of mobile adsorption are offered to predict the adsorption temperature, T
ads, of a heavy-element (or its compound) with respect to T
ads of its lighter homolog (or the same type of compound). A case of adsorption of OsO4 and HsO4 on an inert (quartz or silicon nitride) surface of a chromatography column is taken, as an example. The influence of various properties of the adsorbate, such as molecular weight and size, on T
ads is analyzed to show that those factors should not be ignored in intentionally accurate predictions of T
ads. A comparison of the desorption constants of OsO4 and HsO4 obtained with the use of the calculated spectroscopic properties shows that HsO4 should be significantly more volatile than OsO4, mainly due to the entropy factor.
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Sylwester E, Gregorich K, Lee D, Kadkhodayan B, Türler A, Adams J, Kacher C, Lane M, Laue C, McGrath C. On-line gas chromatographic studies of Rf, Zr, and Hf bromides. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2000.88.12.837] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Heavy Element Volatility Instrument (HEVI), an on-line isothermal gas chromatography system, has been used to separate the volatile bromide compounds of the group 4 elements Zr and Hf and the transactinide Rf according to their volatilities, and to provide data on the gas phase chemical properties of very short-lived isotopes in amounts as low as a few atoms. For these studies261Rf was produced via the248Cm(18O, 5n) reaction.165-167Hf was produced via the reactionnatEu(19F, xn), and85Zr was produced via thenatCu(28Si, 3p3n) reaction. The half-life for261Rf was measured to be 75±7 seconds.A Monte Carlo code was used to deduce the enthalpy of adsorption (ΔHa) from the observed volatility and parameters of the chromatography system. The resulting adsorption enthalpies for the Zr, Hf, and Rf tetrabromides are: -108±5 kJ · mol-1, -113±5 kJ · mol-1 and -87±7 kJ · mol-1, respectively.Volatilities of the group 4 bromides support the conclusion from previous results for the group 4 chlorides that Rf deviates from the trend expected by simple extrapolation of the properties of its lighter homologs in the periodic table. The group 4 bromides are also observed to be less volatile than their respective chlorides, as predicted by relativistic calculations.
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Yakushev AB, Zvara I, Oganessian YT, Belozerov AV, Dmitriev SN, Eichler B, Hübener S, Sokol EA, Türler A, Yeremin AV, Buklanov GV, Chelnokov ML, Chepigin VI, Gorshkov VA, Gulyaev AV, Lebedev VY, Malyshev ON, Popeko AG, Soverna S, Szeglowski Z, Timokhin SN, Tretyakova SP, Vasko VM, Itkis MG. Chemical identification and properties of element 112. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.91.8.433.20010] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Summary
We present results of the second experiment on the chemical identification of element 112. Similar to the first test in 2000, we aimed at the production of the spontaneously fissioning 283112 nuclei with T
1/2≈3min. A natU3O8 (with some Nd) target, 2mg of U/cm2 thick, was bombarded with 233-MeV 48Ca ions (the energy in the middle of the target layer). The nuclei recoiling from the target were thermalized in flowing helium. The target chamber was connected through a 25m long capillary to detectors of α-particles and fission fragments. All the equipment and detectors were kept at ambient temperature. According to the test experiments, of all the heavy elements produced in the bombardment, only Hg, Rn and At could be transported to the detectors. The first detecting device was similar to that used earlier – an assembly of 8 pairs of PIPS detectors coated with gold. Here one would observe the decay of element 112 atoms if they like Hg adsorbed on gold. The atoms which were not retained and freely passed through the PIPS detectors entered a new, flow-through ionization chamber, 5000 cm3 in volume, optimized for detecting fission fragments. The PIPS detectors and the ionization chamber were placed inside a large assembly of 3He – filled neutron counters to detect prompt neutrons from the fission events. In 22.5 days, a beam dose of 2.8×1018 ions was accumulated. More than 95 of the simultaneously produced α-active 185Hg (T
1/2=49 s) were found deposited already on the first pair of PIPS detectors; meanwhile, all the PIPSs did not detect any fission event. In the ionization chamber, eight fission events were observed in coincidence with neutron counts while the expected background was insignificant. Hence, the spontaneous fissions of the volatile activity can be conclusively attributed to the decay of element 112 produced in the fusion reaction 48Ca+ 238U, and formerly observed in Dubna physical experiments. Evaluation of the experimental data in terms of the adsorption enthalpies indicates much weaker interaction of element 112 with Au than that of Hg. One can conclude that in the given chemical environment, element 112 behaves like Rn rather than like Hg. The formation cross section of 283112 estimated from the data amounts to several pb. The experiments were carried out at the Flerov Laboratory of Nuclear Reactions at JINR in November–December 2001.
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Sudowe R, Calvert M, Düllmann CE, Farina LM, Folden CM, Gregorich KE, Gallaher SEH, Hoffman DC, Nelson SL, Phillips DC, Schwantes JM, Wilson RE, Zielinski PM, Nitsche H. Extraction of short-lived zirconium and hafnium isotopes using crown ethers: A model system for the study of rutherfordium. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2006.94.3.123] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Summary
The extraction of zirconium and hafnium from hydrochloric acid media was studied using the crown ethers dibenzo-18-crown-6 (DB18C6), dicyclohexano-18-crown-6 (DC18C6) and dicyclohexano-24-crown-8 (DC24C8) as extractants. The goal was to find an extraction system that exhibits a high selectivity between the members of group 4 of the periodic table and is suitable for the study of rutherfordium. It was found that Zr and Hf are both extracted using DB18C6, DC18C6 and DC24C8. The extraction yield increases with increasing acid concentration and increasing concentration of crown ether. The extracted species most likely consists of an ion-association complex formed between a Zr or Hf chloro complex and a hydronium crown ether complex. Conditions can be found for each extractant that provide for the separation of Zr from Hf. This selective separation between Zr and Hf makes the extraction with crown ethers from HCl well suited to study the extraction behaviour of Rf and compare it to the behaviour of Zr and Hf. These extraction systems can be used to determine whether the extraction behaviour of Rf is similar to Zr, similar to Hf or follows the trend established by the lighter homologs. The extraction kinetics are fast enough for the study of the 78-s isotope 261mRf.
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Abstract
The aqueous chemistry of the first three transactinide elements is briefly reviewed with special emphasis given to recent experimental results. Short introductory remarks are discussing the atom-at-a-time situation of transactinide chemistry as a result of low production cross-sections and short half-lives. In general, on-line experimental techniques and, more specifically, the Automated Rapid Chemistry Apparatus, ARCA, are presented. Present and future developments of experimental techniques and resulting perspectives are outlined at the end. The central part is mainly focussing on hydrolysis and complex formation aspects of the superheavy group 4, 5, and 6 transition metals with F-and Cl-anions. Experimental results are compared with the behaviour of lighter homologuous elements and with relativistic calculations. It will be shown that the chemical behaviour of the first superheavy elements is already strongly influenced by relativistic effects. While it is justified to place rutherfordium, dubnium and seaborgium in the Periodic Table of the Elements into group 4, 5 and 6, respectively, it is no more possible to deduce from this position in detail the chemical properties of these transactinide or superheavy elements.
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Eichler R, Eichler B, Gäggeler HW, Jost D, Piguet D, Türler A. Gas phase chemistry of technetium and rhenium oxychlorides. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2000.88.2.087] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The chloride and oxychloride chemistry of the group 7 elements Tc and Re was investigated in order to develop an experimental approach to a gas chemical characterisation of bohrium (Bh, element 107). In thermochromatography experiments with trace amounts of101,104Tc and183,184Re the formation of one volatile compound was observed in O2/HCl containing carrier gas, which was attributed to MO3Cl (M = Tc, Re). From the measured deposition temperatures the adsorption enthalpies on quartz surfaces ΔHads(TcO3Cl) = -51 ± 3 kJ/mol and ΔHads(ReO3Cl) = -62 ± 3 kJ/mol were evaluated. The sublimation enthalpies were derived using an empirical correlation between Δ Hadsand ΔHsubl: ΔHsubl(TcO3Cl) = 49±10 kJ/mol and ΔHsubl(ReO3Cl) = 67±10 kJ/mol. A fast gas chemical separation technique for highly volatile compounds of short-lived isotopes based on isothermal gas solid adsorption chromatography (OLGA-principle) was developed. With a modified OLGA device, model studies with the short-lived nuclides106,107,108Tc and169,170,174,176Re were carried out in preparation of an experimental gas chemical investigation of bohrium (Bh, element 107). Separation times of less than 3 s were achieved. A good separation of the oxychlorides of group 7 elements from chloride and oxychloride compounds of152-155Er,151-154Ho (as models for actinide elements),98-101Nb,99-102Zr (as models for light transactinide elements),218Po, and214Bi was accomplished in this chemical system.
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Toyoshima A, Kasamatsu Y, Tsukada K, Asai M, Kitatsuji Y, Ishii Y, Toume H, Nishinaka I, Haba H, Ooe K, Sato W, Shinohara A, Akiyama K, Nagame Y. Oxidation of element 102, nobelium, with flow electrolytic column chromatography on an atom-at-a-time scale. J Am Chem Soc 2009; 131:9180-1. [PMID: 19514720 DOI: 10.1021/ja9030038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report here on the successful oxidation of element 102, nobelium (No), on an atom-at-a-time scale in 0.1 M alpha-hydroxyisobutyric acid (alpha-HIB) solution using a newly developed technique, flow electrolytic column chromatography. It is found that the most stable ion, No(2+), is oxidized to No(3+) within 3 min and that the oxidized No complex with alpha-HIB holds the trivalent state in the column above an applied potential of 1.0 V.
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Haba H, Akiyama K, Tsukada K, Asai M, Toyoshima A, Yaita T, Hirata M, Sueki K, Nagame Y. Chloride Complexation of Zr and Hf in HCl Investigated by Extended X-ray Absorption Fine Structure Spectroscopy: Toward Characterization of Chloride Complexation of Element 104, Rutherfordium (Rf). BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2009. [DOI: 10.1246/bcsj.82.698] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Haba H, Kaji D, Komori Y, Kudou Y, Morimoto K, Morita K, Ooe K, Ozeki K, Sato N, Shinohara A, Yoneda A. RIKEN Gas-filled Recoil Ion Separator (GARIS) as a Promising Interface for Superheavy Element Chemistry—Production of Element 104,261Rf, Using the GARIS/Gas-jet System—. CHEM LETT 2009. [DOI: 10.1246/cl.2009.426] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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38
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Fan F, Lei FA, Zhang LN, Lin MS, Bai J, Wu XL, Ding HJ, Li XF, Ding YQ, Qin Z. Extraction behavior of short-lived isotopes of Mo/W using α-benzoinoxime: A model system for the study of seaborgium. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2009.1624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Gates JM, Stavsetra L, Sudowe R, Ali MN, Calvert M, Dragojevic I, Dvorak J, Dvorakova Z, Ellison PA, Garcia MA, Gregorich KE, et al.. Extraction of niobium and tantalum isotopes using organophosphorus compounds. Part II – Extraction of “carrier-free” concentrations from HCl/LiCl solutions. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2009.1584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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40
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Gates JM, Sudowe R, Stavsetra L, Ali MN, Calvert M, Dragojevic I, Ellison PA, Garcia MA, Gharibyan N, Gregorich KE, Nelson SL, et al.. Extraction of niobium and tantalum isotopes using organophosphorus compounds. Part I – Extraction of “carrier-free” metal concentrations from HCl solutions. RADIOCHIM ACTA 2009. [DOI: 10.1524/ract.2009.1583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Eichler R, Aksenov NV, Belozerov AV, Bozhikov GA, Chepigin VI, Dmitriev SN, Dressler R, Gäggeler HW, Gorshkov AV, Itkis MG, Haenssler F, Laube A, Lebedev VY, Malyshev ON, Oganessian YT, Petrushkin OV, Piguet D, Popeko AG, Rasmussen P, Shishkin SV, Serov AA, Shutov AV, Svirikhin AI, Tereshatov EE, Vostokin GK, Wegrzecki M, Yeremin AV. Thermochemical and physical properties of element 112. Angew Chem Int Ed Engl 2008; 47:3262-6. [PMID: 18338360 DOI: 10.1002/anie.200705019] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Robert Eichler
- Labor für Radio- und Umweltchemie, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland.
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Eichler R, Aksenov N, Belozerov A, Bozhikov G, Chepigin V, Dmitriev S, Dressler R, Gäggeler H, Gorshkov A, Itkis M, Haenssler F, Laube A, Lebedev V, Malyshev O, Oganessian Y, Petrushkin O, Piguet D, Popeko A, Rasmussen P, Shishkin S, Serov A, Shutov A, Svirikhin A, Tereshatov E, Vostokin G, Wegrzecki M, Yeremin A. Thermochemische und physikalische Eigenschaften von Element 112. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200705019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Yu YJ, Dong CZ, Li JG, Fricke B. The excitation energies, ionization potentials, and oscillator strengths of neutral and ionized species of Uuq (Z=114) and the homolog elements Ge, Sn, and Pb. J Chem Phys 2008; 128:124316. [DOI: 10.1063/1.2838985] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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Ishii Y, Toyoshima A, Tsukada K, Asai M, Toume H, Nishinaka I, Nagame Y, Miyashita S, Mori T, Suganuma H, Haba H, Sakamaki M, Goto SI, Kudo H, Akiyama K, Oura Y, Nakahara H, Tashiro Y, Shinohara A, Schädel M, Brüchle W, Pershina V, Kratz JV. Fluoride Complexation of Element 104, Rutherfordium (Rf), Investigated by Cation-exchange Chromatography. CHEM LETT 2008. [DOI: 10.1246/cl.2008.288] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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45
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Toyoshima A, Haba H, Tsukada K, Asai M, Akiyama K, Goto S, Ishii Y, Nishinaka I, Sato TK, Nagame Y, Sato W, Tani Y, Hasegawa H, Matsuo K, Saika D, Kitamoto Y, Shinohara A, Ito M, Saito J, Kudo H, Yokoyama A, Sakama M, Sueki K, Oura Y, Nakahara H, Schädel M, Brüchle W, Kratz JV. Hexafluoro complex of rutherfordium in mixed HF/HNO3 solutions. RADIOCHIM ACTA 2008. [DOI: 10.1524/ract.2008.1474] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Thirty years of relativistic self-consistent field theory for molecules: relativistic and electron correlation effects for atomic and molecular systems of transactinide superheavy elements up to ekaplutonium E126 with g-atomic spinors in the ground state configuration. Theor Chem Acc 2007. [DOI: 10.1007/s00214-007-0335-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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47
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de Macedo LGM, Sambrano JR, de Souza AR, Borin AC. All electron fully relativistic Dirac–Fock calculation for darmstadtium carbide using prolapse free basis set. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.04.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Sarpe-Tudoran C, Fricke B, Anton J, Persina V. Adsorption of superheavy elements on metal surfaces. J Chem Phys 2007; 126:174702. [PMID: 17492874 DOI: 10.1063/1.2727447] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Fully relativistic four-component density functional theory with the general gradient approximation calculations have been performed to determine the adsorption energy and position of the superheavy element 112 on a Au surface. Extended cluster as well as embedded cluster calculations were used to simulate the surface which allow for the top, bridge, and hollow adsorption sites without losing the advantage of symmetry considerations. Comparison with analogous calculations of the adsorption of the homologue element Hg allows to predict the adsorption of element 112 at a bridge site with a binding energy of 0.67 eV.
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Hancock RD, Bartolotti LJ, Kaltsoyannis N. Density Functional Theory-Based Prediction of Some Aqueous-Phase Chemistry of Superheavy Element 111. Roentgenium(I) Is the ‘Softest' Metal Ion. Inorg Chem 2006; 45:10780-5. [PMID: 17173436 DOI: 10.1021/ic061282s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A previous approach (Hancock, R. D.; Bartolotti, L. J. Inorg. Chem. 2005, 44, 7175) using DFT calculations to predict log K1 (formation constant) values for complexes of NH3 in aqueous solution was used to examine the solution chemistry of Rg(I) (element 111), which is a congener of Cu(I), Ag(I), and Au(I) in Group 1B. Rg(I) has as its most stable presently known isotope a t(1/2) of 3.6 s, so that its solution chemistry is not easily accessible. LFER (Linear free energy relationships) were established between DeltaE(g) calculated by DFT for the formation of monoamine complexes from the aquo ions in the gas phase, and DeltaG(aq) for the formation of the corresponding complexes in aqueous solution. For M2+, M3+, and M4+ ions, the gas-phase reaction was [M(H2O)6]n+(g) + NH3(g) = [M(H2O)5NH3]n+(g) + H2O(g) (1), while for M+ ions, the reaction was [M(H2O)2]+(g) + NH3(g) = [M(H2O)NH3]+(g) + H2O(g) (2). A value for DeltaG(aq) and for DeltaE for the formation of M = Cu2+ in reaction 1, not obtained previously, was calculated by DFT and shown to correlate well with the LFER obtained previously for other M2+ ions, supporting the LFER approach used here. The simpler use of DeltaE values instead of DeltaG(aq) values calculated by DFT for formation of monoamine complexes in the gas phase leads to LFER as good as the DeltaG-based correlations. Values of DeltaE were calculated by DFT to construct LFER with M+ = H+, and the Group 1B metal ions Cu+, Ag+, Au+, and Rg+, and with L = NH3, H2S, and PH3 in reaction 3: [M(H2O)2]+(g) + L(g) = [M(H2O)L]+g) + H2O(g) (3). Correlations involving DeltaE calculated by DMol3 for H+, Cu+, Ag+, and Au+ could reliably be used to construct LFER and estimate unknown log K1 values for Rg(I) complexes of NH3, PH3, and H2S calculated using the ADF (Amsterdam Density Functional) code. Log K1 values for Rg(I) complexes are predicted that suggest the Rg(I) ion to be a very strong Lewis acid that is extremely "soft" in the Pearson hard and soft acids and bases sense.
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Affiliation(s)
- Robert D Hancock
- Department of Chemistry and Biochemistry, University of North Carolina-Wilmington, Wilmington, NC 28403, USA
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Abstract
The number of chemical elements has increased considerably in the last few decades. Most excitingly, these heaviest, man-made elements at the far-end of the Periodic Table are located in the area of the long-awaited superheavy elements. While physical techniques currently play a leading role in these discoveries, the chemistry of superheavy elements is now beginning to be developed. Advanced and very sensitive techniques allow the chemical properties of these elusive elements to be probed. Often, less than ten short-lived atoms, chemically separated one-atom-at-a-time, provide crucial information on basic chemical properties. These results place the architecture of the far-end of the Periodic Table on the test bench and probe the increasingly strong relativistic effects that influence the chemical properties there. This review is focused mainly on the experimental work on superheavy element chemistry. It contains a short contribution on relativistic theory, and some important historical and nuclear aspects.
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Affiliation(s)
- Matthias Schädel
- KPII-Kernchemie, Gesellschaft für Schwerionenforschung mbH, Planckstrasse 1, 64291 Darmstadt, Germany.
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