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Guo Y, Liu H, Cao H, Dong X, Wang Z, Chen J, Xu C. Complexation of uranyl with benzoic acid in aqueous solution at variable temperatures: potentiometry, spectrophotometry and DFT calculations. Dalton Trans 2023; 52:11265-11271. [PMID: 37526577 DOI: 10.1039/d3dt01896b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Abstract
Investigation of the fundamental coordination chemistry between U(VI) and simple organic ligands is important to understand the chemical behavior of U(VI) in the natural environment and separation processes. In this work, the complexation of U(VI) with a common carboxylic acid, benzoic acid, has been systematically investigated through potentiometry, spectrometry and DFT calculations. Three successive complexes (UO2L+, UO2L2 and UO2L3-, L = benzoate ion) between U(VI) and benzoic acid are successfully identified in aqueous solution and their corresponding thermodynamic parameters (stability constant, enthalpy and entropy) are determined. Notably, this is the first time that the previously missing 1 : 2 and 1 : 3 (U to L) complexes in aqueous solution and their complexation thermodynamics have been reported, which would aid in more accurate prediction of the chemical behavior of U(VI) in the presence of benzoic acid. Moreover, the structures of the complexes are elucidated using DFT calculations, which show that benzoic acid coordinates to U(VI) in a bidentate form in all the complexes.
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Affiliation(s)
- Yuxiao Guo
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Haiwang Liu
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Hong Cao
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Xue Dong
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Zhipeng Wang
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Jing Chen
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
| | - Chao Xu
- Institute of Nuclear and New Energy Technology, Tsinghua University, 100084, Beijing, China.
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Choi S, Yun JI. Spectroscopic Study on Aqueous Uranyl(VI) Complexes with Methoxy- and Methylbenzoates: Electronic and Steric Effects of the Substituents. Inorg Chem 2020; 59:15194-15203. [PMID: 33030337 DOI: 10.1021/acs.inorgchem.0c02173] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aqueous complexation of uranyl(VI) ions with methoxy- and methylbenzoates in 0.1 M NaClO4 solutions was studied by means of UV-vis absorption and Raman spectroscopy. The predominance of 1:1 complexation (uranyl to ligand) was verified for all uranyl carboxylates under acidic conditions (-log [H+] < 3.2), and absorption spectra, stability constants, and symmetric stretching frequencies of the uranyl group of the complexes were determined for the first time. For meta- and para-substituted benzoates, a linear free energy relationship (LFER) was observed between the equilibrium constants for the protonation (log βP) and uranyl complexation (log βU) reactions, and the electronic effects of the substituents were successfully described by the Hammett equation. In the case of ortho-substituted benzoates, the stability constant of uranyl 2-methoxybenzoate is slightly lower than the LFER trend, which is generally explained by the destabilization of cross-conjugation in the uranyl complex due to the steric hindrance between the reaction center and adjacent methoxy group. On the contrary, the stability constant of uranyl 2-methylbenzoate is comparable to the LFER trend, implying that the steric effect is relatively insignificant for the smaller methyl group. The utility of such thermodynamic correlations between the uranyl-substituted benzoates is useful for the molecular understanding and predictive modeling of chemical interactions between actinyl(VI) ions and various organic carboxyl groups.
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Affiliation(s)
- Seonggyu Choi
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
| | - Jong-Il Yun
- Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 34141, Republic of Korea
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Choi S, Yun JI. Spectrophotometric study of the uranyl monobenzoate complex at moderate ionic strength. Polyhedron 2019. [DOI: 10.1016/j.poly.2019.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Srivastava A, Dumpala RMR, Rawat N, Tomar B. Electrochemical, spectroscopic and theoretical studies on redox speciation of neptunium with phenylphosphonic acid. Inorganica Chim Acta 2018. [DOI: 10.1016/j.ica.2018.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Sauge-Merle S, Brulfert F, Pardoux R, Solari PL, Lemaire D, Safi S, Guilbaud P, Simoni E, Merroun ML, Berthomieu C. Structural Analysis of Uranyl Complexation by the EF-Hand Motif of Calmodulin: Effect of Phosphorylation. Chemistry 2017; 23:15505-15517. [DOI: 10.1002/chem.201703484] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Indexed: 01/03/2023]
Affiliation(s)
- Sandrine Sauge-Merle
- CEA; CNRS; Aix-Marseille Université; UMR 7265 Biologie Végétale et Microbiologie Environnementales; Laboratoire des Interactions Protéine Métal; 13108 Saint-Paul-lez-Durance France
| | - Florian Brulfert
- Institut de Physique Nucléaire d'Orsay, CNRS-IN2P3; Univ. Paris-Sud, Univ. Paris-Saclay; 91405 Orsay France
| | - Romain Pardoux
- CEA; CNRS; Aix-Marseille Université; UMR 7265 Biologie Végétale et Microbiologie Environnementales; Laboratoire des Interactions Protéine Métal; 13108 Saint-Paul-lez-Durance France
| | - Pier Lorenzo Solari
- MARS beamline; Synchrotron SOLEIL; L'Orme des Merisiers, Saint-Aubin; 91192 Gif-sur-Yvette Cedex France
| | - David Lemaire
- CEA; CNRS; Aix-Marseille Université; UMR 7265 Biologie Végétale et Microbiologie Environnementales; Laboratoire des Interactions Protéine Métal; 13108 Saint-Paul-lez-Durance France
| | - Samir Safi
- Institut de Physique Nucléaire d'Orsay, CNRS-IN2P3; Univ. Paris-Sud, Univ. Paris-Saclay; 91405 Orsay France
| | - Philippe Guilbaud
- CEA, Nuclear Energy Division; Research Department on Mining and fuel Recycling Processes (LILA); BP17171 30207 Bagnols-sur-Cèze France
| | - Eric Simoni
- Institut de Physique Nucléaire d'Orsay, CNRS-IN2P3; Univ. Paris-Sud, Univ. Paris-Saclay; 91405 Orsay France
| | | | - Catherine Berthomieu
- CEA; CNRS; Aix-Marseille Université; UMR 7265 Biologie Végétale et Microbiologie Environnementales; Laboratoire des Interactions Protéine Métal; 13108 Saint-Paul-lez-Durance France
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Srivastava A, Kumar P, Tomar BS. Redox speciation of uranium with phenylphosphonic acid (PPA) in aqueous medium. RADIOCHIM ACTA 2016. [DOI: 10.1515/ract-2016-2652] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Studies on complexation of uranium with organophosphorous ligands in aquatic systems are important from point of view of mobility of uranium in environment. In the present paper, we report the results of complexation of U(VI) by a model ligand for organophosphorus functionalities in humic substances (HS), that is, phenylphosphonic acid (PPA), using electro analytical techniques. The UO2
2+ has been found to form 1:1 and 1:2 complexes with mono-protonated PPA (HPhPO3
−) and 1:1 complex with non-protonated PPA, (PhPO3)2−, with the latter complex (UO2PhPO3) dominating over the other two species. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to investigate the redox behavior of UO2PhPO3 species and to explore the kinetics of its reduction by evaluating heterogeneous electron-transfer kinetic (D, k
s and α) parameters. The diffusion coefficient (D) value was found to be 6.76×10−5 cm2 s−1 and 5.03×10−5 cm2 s−1 at pH 5 and 3, respectively, with rate constant, k
s=0.304×10−3 cm/s. Using the DeFord and Hume formalism the stability constant (log β) of UO2PhPO3 was calculated to be (6.98±0.12), which is in agreement with the literature data. Electrospray ionization mass spectrometry (ESI-MS) studies corroborated the existence of UO2PhPO3 complex.
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Affiliation(s)
- Ashutosh Srivastava
- Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400085, India
| | - Pranaw Kumar
- Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400085, India
| | - Bhupendra S. Tomar
- Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400085, India
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Yang Y, Teat SJ, Zhang Z, Luo S, Rao L. Complexation of U(VI) with benzoic acid at variable temperatures (298-353 K): thermodynamics and crystal structures of U(VI)/benzoate complexes. Dalton Trans 2016; 45:384-91. [PMID: 26609903 DOI: 10.1039/c5dt03532e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thermodynamics of the U(VI) complexation with benzoic acid (HL) was studied by spectrophotometry at varied temperatures (298-353 K) with constant ionic strength (1.05 mol kg(-1) NaClO4). Two U(VI) benzoate complexes, UO2L(+) and UO2(OH)L(aq), were identified and their formation constants determined. The formation of both complexes is endothermic and driven exclusively by entropy. Two types of U(VI)/benzoate complex crystals were synthesized from aqueous solutions at different pH and ligand/metal ratios. Their structures were determined by single-crystal X-ray diffractometry. One structure is a 1 : 3 U(VI) benzoate complex (Na[UO2(C7H5O2)3]·2H2O), each benzoate holding a bidentate coordination mode to U(VI) in the equatorial plane of UO2(2+). The other is a U(VI) hydroxobenzoate complex with unique μ3-OH bridging ([(UO2)2(C7H5O2)2(μ3-OH)2]·4H2O). In the structure, each UO2(2+) ion holds five coordination oxygens in its equatorial plane, two carboxylate oxygens from two benzoate ligands and three oxygens from three μ3-OH groups.
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Affiliation(s)
- Yanqiu Yang
- Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900, China and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Simon J Teat
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Zhicheng Zhang
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Shunzhong Luo
- Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics, Mianyang, Sichuan 621900, China
| | - Linfeng Rao
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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10
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Pathak PN, Mohapatra M, Godbole SV. Photoluminescence studies on the complexation of Eu(III) and Tb(III) with acetohydroxamic acid (AHA) in nitrate medium. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:805-809. [PMID: 23892121 DOI: 10.1016/j.saa.2013.06.104] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 06/26/2013] [Accepted: 06/28/2013] [Indexed: 06/02/2023]
Abstract
UREX process has been proposed for selective extraction of U(VI) and Tc(VII) from nitric acid medium (∼1M HNO3) using tri-n-butyl phosphate (TBP) as extractant and retaining Pu, Np and fission products in the aqueous phase. The feasibility of the use of luminescence spectroscopy as a technique to understand the complexation of trivalent f-elements cations viz. Eu(III) and Tb(III) with acetohydroxamic acid (AHA) in nitric acid medium has been examined. The luminescence lifetimes for the 1×10(-3)M Eu(III) and AHA complex system decreased with increased AHA concentration from 116±0.2μs (no AHA) to 1.6±0.1μs (0.1M AHA) which was attributed to dynamic quenching. The corrected fluorescence intensities were used to calculate the stability constant (log K) for the formation of 1:1 Eu(3+)-AHA complex as 1.42±0.64 under the conditions of this study. By contrast, the Tb(III)-AHA system at pH 3 (HNO3) did not show any significant variation in the life times of the excited state (364±9μs) suggesting the absence of dynamic quenching. The spectral changes in Tb(III)-AHA system showed the formation of 1:1 complex (log K: 1.72±0.21). These studies suggest that the extent of AHA complexation with the rare earth elements will be insignificant as compared to tetravalent metal ions Pu(IV) and Np(IV) under UREX process conditions.
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Affiliation(s)
- P N Pathak
- Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India.
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11
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Galindo C, Del Nero M. Trace level uranyl complexation with phenylphosphonic acid in aqueous solution: direct speciation by high resolution mass spectrometry. Inorg Chem 2013; 52:4372-83. [PMID: 23527599 DOI: 10.1021/ic302494a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The complexation of U(VI) by organic P-containing ligands in humic substances (HS) is an important issue of uranyl mobility in soil. We have investigated the complexation of uranyl by a model ligand for aromatic phosphorus functionalities in HS, phenylphosphonic acid, by using ultrahigh resolution electrospray ionization-mass spectrometry (ESI-MS). The high sensitivity permitted to investigate the complexation of trace level uranyl and to explore directly in the native aqueous solutions the nature of the uranyl-phenylphosphonate complexes. Positive identification of the complexes coexisting in solutions with low pH and varying ligand-to-metal ratio was achieved thanks to the high resolving power, high mass accuracy, and reliability of ion abundance of the technique. The positively charged and neutral uranyl species were detected simultaneously on negative ion mass spectra, evidencing formation of three types of U(VI)-phenylphosphonate complexes. Two complexes with a metal-to-ligand stoichiometry of 1:1 (in the monoprotonated and nonprotonated forms) existed in solutions at pH 3-5, and a 1:2 complex was additionally formed at relatively high ligand-to-metal ratio. A strategy based on the use of uranyl-phosphate solution complexes as internal standards was developed to determine from the ESI(-)MS results the stability constants of the complexes, which were calculated to be log K111 = 3.4 ± 0.2 for UO2(HPhPO3)(+), log K101 = 7.1 ± 0.1 for UO2PhPO3, and log K112 = 7.2 ± 0.2 for UO2(HPhPO3)2. The speciation model presented here suggests that organic P existing at low concentration in HS is involved significantly in binding by humic and fulvic acids of trace level uranyl in soil.
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Affiliation(s)
- Catherine Galindo
- Institut Pluridisciplinaire Hubert Curien, UMR 7178 CNRS/UdS, 23 rue du Loess, BP 28, 67037 Strasbourg Cedex 2, France.
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12
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Lütke L, Moll H, Bernhard G. A new uranyl benzoate species characterized by different spectroscopic techniques. RADIOCHIM ACTA 2012. [DOI: 10.1524/ract.2012.1916] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
For the first time in the aqueous phase the existence of a U(VI)-benzoate complex with a 1:2 stoichiometry could be proven. Using UV-Vis spectroscopy and especially cryo time-resolved laser-induced fluorescence spectroscopy (TRLFS) it was possible to characterize this complex in detail.
Room temperature TRLFS measurements revealed a static as well as a dynamic ligand-initiated quench process in the U(VI)-benzoic acid system. At these conditions no luminescence emission resulting from complex formation was found. Consequently cryo TRLFS was applied to increase the maximum detectable benzoate:U(VI) ratio. By this for the first time a luminescence spectrum of the 1:2 U(VI)-benzoate complex could be determined. This species is characterized by emission bands at 467, 485, 505, 526, and 550 nm which are blue-shifted compared to the ones of the UO2
2+ ion. The luminescence lifetime of the 1:2 complex amounts to 9.21±0.01 μs at −18 ºC compared to 150.4±0.5 μs for UO2
2+.
The stability constant of the newly found species log β
120 has been calculated to be 4.48±0.24. The stability constant of the 1:1 complex was validated to amount to 2.64±0.19. UV-Vis spectroscopy combined with factor analysis yielded the molar absorption spectrum of the 1:2 U(VI)-benzoate species which is characterized by absorption bands at 406, 418, 432.5, 447, and 461 nm and a molar absorption coefficient of 22 L mol−1 cm−1.
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Affiliation(s)
| | - H. Moll
- Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Radiochemistry, Dresden, Deutschland
| | - G. Bernhard
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiochemistry, Dresden, Deutschland
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Qin W, Xu Y, Liu H, Ren L, Yang C. Flotation and Surface Behavior of Cassiterite with Salicylhydroxamic Acid. Ind Eng Chem Res 2011. [DOI: 10.1021/ie200800d] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wenqing Qin
- School of Minerals Processing and Bioengineering and Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Yangbao Xu
- School of Minerals Processing and Bioengineering and Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Hui Liu
- School of Minerals Processing and Bioengineering and Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Liuyi Ren
- School of Minerals Processing and Bioengineering and Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, Hunan 410083, People's Republic of China
| | - Congren Yang
- School of Minerals Processing and Bioengineering and Key Laboratory of Biometallurgy of Ministry of Education, Central South University, Changsha, Hunan 410083, People's Republic of China
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Wiebke J, Weigand A, Weissmann D, Glorius M, Moll H, Bernhard G, Dolg M. Combined Computational and Experimental Study of Uranyl(VI) 1:2 Complexation by Aromatic Acids. Inorg Chem 2010; 49:6428-35. [DOI: 10.1021/ic902496u] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jonas Wiebke
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Anna Weigand
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Daniel Weissmann
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
| | - Maja Glorius
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Henry Moll
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Gert Bernhard
- Forschungszentrum Dresden−Rossendorf e.V., Institut für Radiochemie, P.O. Box 510119, D-01314 Dresden, Germany
| | - Michael Dolg
- Institut für Theoretische Chemie, Department für Chemie, Universität zu Köln, Greinstrasse 4, D-50939 Köln, Germany
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Glorius M, Moll H, Bernhard G. Complexation of curium(III) with hydroxamic acids investigated by time-resolved laser-induced fluorescence spectroscopy. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.04.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Wiebke J, Moritz A, Glorius M, Moll H, Bernhard G, Dolg M. Complexation of Uranium(VI) with Aromatic Acids in Aqueous Solution: A Combined Computational and Experimental Study. Inorg Chem 2008; 47:3150-7. [DOI: 10.1021/ic702162r] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jonas Wiebke
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Anna Moritz
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Maja Glorius
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Henry Moll
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Gert Bernhard
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
| | - Michael Dolg
- Institut für Theoretische Chemie, Universität zu Köln, Greinstr. 4, D-50939 Köln, Germany, and Institut für Radiochemie, Forschungszentrum Dresden-Rossendorf e.V., P.O. Box 510119, D-01314 Dresden, Germany
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