1
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Preferential recovery and separation of rhodium in the concentrated hydrochloric acid using thin-layer oil membrane extraction based on laminar flow. Chem Eng Res Des 2023. [DOI: 10.1016/j.cherd.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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2
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Mironenko RM, Likholobov VA, Belskaya OB. Nanoglobular carbon and palladium - carbon catalysts for liquid-phase hydrogenation of organic compounds. RUSSIAN CHEMICAL REVIEWS 2022. [DOI: 10.1070/rcr5017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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3
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Nayak S, Kumal RR, Liu Z, Qiao B, Clark AE, Uysal A. Origins of Clustering of Metalate-Extractant Complexes in Liquid-Liquid Extraction. ACS APPLIED MATERIALS & INTERFACES 2021; 13:24194-24206. [PMID: 33849269 DOI: 10.1021/acsami.0c23158] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Effective and energy-efficient separation of precious and rare metals is very important for a variety of advanced technologies. Liquid-liquid extraction (LLE) is a relatively less energy intensive separation technique, widely used in separation of lanthanides, actinides, and platinum group metals (PGMs). In LLE, the distribution of an ion between an aqueous phase and an organic phase is determined by enthalpic (coordination interactions) and entropic (fluid reorganization) contributions. The molecular scale details of these contributions are not well understood. Preferential extraction of an ion from the aqueous phase is usually correlated with the resulting fluid organization in the organic phase, as the longer-range organization increases with metal loading. However, it is difficult to determine the extent to which organic phase fluid organization causes, or is caused by, metal loading. In this study, we demonstrate that two systems with the same metal loading may impart very different organic phase organizations and investigate the underlying molecular scale mechanism. Small-angle X-ray scattering shows that the structure of a quaternary ammonium extractant solution in toluene is affected differently by the extraction of two metalates (octahedral PtCl62- and square-planar PdCl42-), although both are completely transferred into the organic phase. The aggregates formed by the metalate-extractant complexes (approximated as reverse micelles) exhibit a more long-range order (clustering) with PtCl62- compared to that with PdCl42-. Vibrational sum frequency generation spectroscopy and complementary atomistic molecular dynamics simulations on model Langmuir monolayers indicate that the two metalates affect the interfacial hydration structures differently. Furthermore, the interfacial hydration is correlated with water extraction into the organic phase. These results support a strong relationship between the organic phase organizational structure and the different local hydration present within the aggregates of metalate-extractant complexes, which is independent of metalate concentration.
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Affiliation(s)
- Srikanth Nayak
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Raju R Kumal
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Zhu Liu
- Department of Chemistry, Washington State University, Pullman, Washington 99164, United States
| | - Baofu Qiao
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Aurora E Clark
- Department of Chemistry, Washington State University, Pullman, Washington 99164, United States
| | - Ahmet Uysal
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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4
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Kurt B, Temel H, Atlan M, Kaya S. Synthesis, characterization, DNA interaction and docking studies of novel Schiff base ligand derived from 2,6-diaminopyridine and its complexes. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.127928] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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5
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Ab initio MRCI study on potential energy curves for a single Cl loss from the palladium tetrachloride anion PdCl42−. Chem Phys Lett 2020. [DOI: 10.1016/j.cplett.2020.137288] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Torrejos REC, Nisola GM, Min SH, Han JW, Koo S, Parohinog KJ, Lee S, Kim H, Chung WJ. Aqueous Synthesis of 14-15-Membered Crown Ethers with Mixed O, N and S Heteroatoms: Experimental and Theoretical Binding Studies with Platinum-Group Metals. Chempluschem 2019; 84:210-221. [DOI: 10.1002/cplu.201800541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/22/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Rey Eliseo C. Torrejos
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
| | - Grace M. Nisola
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
| | - Sang Hoon Min
- Department of Chemical Engineering; University of Seoul; Seoul 02504 South Korea
| | - Jeong Woo Han
- Department of Chemical Engineering; Pohang University of Science and Technology (POSTECH); Pohang 37673 South Korea
| | - Sangho Koo
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
- Department of Chemistry; Myongji University; Yongin Science Campus 17058 South Korea
| | - Khino J. Parohinog
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
| | - Seongpoong Lee
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
| | - Hern Kim
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
| | - Wook-Jin Chung
- Energy and Environment Fusion Technology Center (E FTC) Department of Energy Science and Technology (DEST); Myongji University Yongin Science Campus; 17058 South Korea
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7
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Engelbrecht L, Mocci F, Laaksonen A, Koch KR. 195Pt NMR and Molecular Dynamics Simulation Study of the Solvation of [PtCl 6] 2- in Water-Methanol and Water-Dimethoxyethane Binary Mixtures. Inorg Chem 2018; 57:12025-12037. [PMID: 30215514 DOI: 10.1021/acs.inorgchem.8b01554] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The experimental 195Pt NMR chemical shift, δ(195Pt), of the [PtCl6]2- anion dissolved in binary mixtures of water and a fully miscible organic solvent is extremely sensitive to the composition of the mixture at room temperature. Significantly nonlinear δ(195Pt) trends as a function of solvent composition are observed in mixtures of water-methanol, or ethylene glycol, 2-methoxyethanol, and 1,2-dimethoxyethane (DME). The extent of the deviation from linearity of the δ(195Pt) trend depends strongly on the nature of the organic component in these solutions, which broadly suggests preferential solvation of the [PtCl6]2- anion by the organic molecule. This simplistic interpretation is based on an accepted view pertaining to monovalent cations in similar binary solvent mixtures. To elucidate these phenomena in detail, classical molecular dynamics computer simulations were performed for [PtCl6]2- in water-methanol and water-DME mixtures using the anionic charge scaling approach to account for the effect of electronic dielectric screening. Our simulations suggest that the simplistic model of preferential solvation of [PtCl6]2- by the organic component as inferred from nonlinear δ(195Pt) trends is not entirely accurate, particularly for water-DME mixtures. The δ(195Pt) trend in these mixtures levels off for high DME mole fractions, which results from apparent preferential location of [PtCl6]2- anions at the borders of water-rich regions or clusters within these inherently micro-heterogeneous mixtures. By contrast in water-methanol mixtures, apparently less pronounced mixed solvent micro-heterogeneity is found, suggesting the experimental δ(195Pt) trend is consistent with a more moderate preferential solvation of [PtCl6]2- anions. This finding underlines the important role of solvent-solvent interactions and micro-heterogeneity in determining the solvation environment of [PtCl6]2- anions in binary solvent mixtures, probed by highly sensitive 195Pt NMR. The notion that preferential solvation of [PtCl6]2- results primarily from competing ion-solvent interactions as generally assumed for monatomic ions, may not be appropriate in general.
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Affiliation(s)
- Leon Engelbrecht
- Department of Chemistry and Polymer Science , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa.,Department of Chemical and Geological Sciences , University of Cagliari , I-09042 Monserrato , Italy.,Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Arrhenius Laboratory , Stockholm University , 10691 Stockholm , Sweden
| | - Francesca Mocci
- Department of Chemical and Geological Sciences , University of Cagliari , I-09042 Monserrato , Italy
| | - Aatto Laaksonen
- Division of Physical Chemistry, Department of Materials and Environmental Chemistry, Arrhenius Laboratory , Stockholm University , 10691 Stockholm , Sweden.,Department of Chemistry-Ångström Laboratory , Uppsala University , Box 538, SE-75121 Uppsala , Sweden
| | - Klaus R Koch
- Department of Chemistry and Polymer Science , Stellenbosch University , Private Bag X1 , Matieland 7602 , South Africa
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8
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Patel A, Tiwari S, Jha PK. Density functional theory based probe of the affinity interaction of saccharide ligands with extra-cellular sialic acid residues. J Biomol Struct Dyn 2018; 37:1545-1554. [PMID: 29624120 DOI: 10.1080/07391102.2018.1461690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Changes in glycosylation pattern leads to malignant transformations among the cells. In combination with upregulated actions of sialyltransferases, it ultimately leads to differential expression of sialic acid (SA) at cell surface. Given its negative charge and localization to extracellular domain, SA has been exploited for the development of targeted theranostics using approaches, such as, cationization and appending recognition saccharides on carrier surface. In this study, we have performed quantum mechanical calculations based on density functional theory (DFT) to study the interaction of saccharides with extracellular SA. Gradient-corrected DFT with the three parameter function (B3) was utilized for the calculation of Lee-Yang-Parr (LYP) correlation function. Atomic charge, vibrational frequencies and energy of the optimized structures were calculated through B3LYP. Our calculations demonstrate a stronger galactose-sialic acid interaction at tumour-relevant low pH and hyperthermic condition. These results support the application of pH responsive delivery vehicles and targeted hyperthermic chemotherapy for eradicating solid tumour deposits. These studies, conducted a priori, can guide the formulation scientists over appropriate choice of ligands and their applications in the design of 'smart' theranostic tools.
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Key Words
- AChE, Acetylcholine Esterase
- ASDase, aspartate semialdehyde dehydrogenase
- B3LYP, Becke 3-Parameter Lee, Yang and Parr
- BACE1, Beta-secretase 1
- BSSE, basis set superposition error
- CK2, casein kinase 2
- CMAS, cytidine monophosphate N-acetylneuraminic acid synthase
- DFT, density functional theory
- EcPLA, Echis carinatus Phospholipase A
- FF, fukui function
- GSK3β, glycogen synthase kinase 3β
- Gal, galactose
- HLG, HOMO-LUMO gap
- HOMO, highest occupied molecular orbital
- LUMO, lowest unoccupied molecular orbital
- MEP, molecular electrostatic potential
- Man, mannose
- NBO, natural bond orbital
- NC, nanocarriers.
- PBA, phenylboronic acid
- SA, sialic acid
- cancer
- density functional theory
- hypersialylation
- recognition saccharides
- targeted theranostics
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Affiliation(s)
- Anjali Patel
- a Department of Physics, Faculty of Science , The Maharaja Sayajirao University of Baroda , Vadodara - 390 002 , India
| | - Sanjay Tiwari
- b Maliba Pharmacy College , UKA Tarsadia University, Gopal-Vidyanagar Campus , Surat , 394350 , India
| | - Prafulla K Jha
- a Department of Physics, Faculty of Science , The Maharaja Sayajirao University of Baroda , Vadodara - 390 002 , India
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9
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Šebesta F, Sláma V, Melcr J, Futera Z, Burda JV. Estimation of Transition-Metal Empirical Parameters for Molecular Mechanical Force Fields. J Chem Theory Comput 2016; 12:3681-8. [DOI: 10.1021/acs.jctc.6b00416] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Filip Šebesta
- Department of Chemical Physics
and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Vladislav Sláma
- Department of Chemical Physics
and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Josef Melcr
- Department of Chemical Physics
and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Zdeněk Futera
- Department of Chemical Physics
and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
| | - Jaroslav V. Burda
- Department of Chemical Physics
and Optics, Faculty of Mathematics and Physics, Charles University, Ke Karlovu 3, 121 16 Prague 2, Czech Republic
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10
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Huang J, Häussinger D, Gellrich U, Seiche W, Breit B, Meuwly M. Hydrogen-Bond and Solvent Dynamics in Transition Metal Complexes: A Combined Simulation and NMR-Investigation. J Phys Chem B 2012; 116:14406-15. [DOI: 10.1021/jp309412r] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jing Huang
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel,
Switzerland, and
| | - Daniel Häussinger
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel,
Switzerland, and
| | - Urs Gellrich
- Institute
für Organische
Chemie und Biochemie, Albert-Ludwigs-Unversität, Freiburg, Germany
| | - Wolfgang Seiche
- Institute
für Organische
Chemie und Biochemie, Albert-Ludwigs-Unversität, Freiburg, Germany
| | - Bernhard Breit
- Institute
für Organische
Chemie und Biochemie, Albert-Ludwigs-Unversität, Freiburg, Germany
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel,
Switzerland, and
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11
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Atanasov M, Comba P, Helmle S, Müller D, Neese F. Zero-Field Splitting in a Series of Structurally Related Mononuclear NiII–Bispidine Complexes. Inorg Chem 2012; 51:12324-35. [DOI: 10.1021/ic3016047] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Mihail Atanasov
- Anorganisch-Chemisches
Institut, Universität Heidelberg, INF 270, D-69120 Heidelberg,
Germany
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse
34-36, D-45470 Mülheim an der Ruhr, Germany
- Institute of General and Inorganic
Chemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Peter Comba
- Anorganisch-Chemisches
Institut, Universität Heidelberg, INF 270, D-69120 Heidelberg,
Germany
| | - Stefan Helmle
- Anorganisch-Chemisches
Institut, Universität Heidelberg, INF 270, D-69120 Heidelberg,
Germany
| | - Dennis Müller
- Anorganisch-Chemisches
Institut, Universität Heidelberg, INF 270, D-69120 Heidelberg,
Germany
| | - Frank Neese
- Max-Planck-Institut für Chemische Energiekonversion, Stiftstrasse
34-36, D-45470 Mülheim an der Ruhr, Germany
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12
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Mori H, Hirayama N, Komeiji Y, Mochizuki Y. Differences in hydration between cis- and trans-platin: Quantum insights by ab initio fragment molecular orbital-based molecular dynamics (FMO-MD). COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2012.02.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Matthews RP, Venter GA, Naidoo KJ. Using Solvent Binding and Dielectric Friction To Interpret the Hydration Behavior of Complex Anions. J Phys Chem B 2011; 115:1045-55. [DOI: 10.1021/jp109976p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Richard P. Matthews
- Scientific Computing Research Unit and Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Gerhard A. Venter
- Scientific Computing Research Unit and Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kevin J. Naidoo
- Scientific Computing Research Unit and Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
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14
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Matthews RP, Naidoo KJ. Experimentally Consistent Ion Association Predicted for Metal Solutions from Free Energy Simulations. J Phys Chem B 2010; 114:7286-93. [DOI: 10.1021/jp911823x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Richard P. Matthews
- Scientific Computing Research Unit, University of Cape Town, Rondebosch 7701, South Africa, and Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
| | - Kevin J. Naidoo
- Scientific Computing Research Unit, University of Cape Town, Rondebosch 7701, South Africa, and Department of Chemistry, University of Cape Town, Rondebosch 7701, South Africa
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15
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Fu CF, Tian SX. Molecular dynamics study of solvation differences between cis- and transplatin molecules in water. J Chem Phys 2010; 132:174507. [DOI: 10.1063/1.3426029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Truflandier LA, Autschbach J. Probing the Solvent Shell with 195Pt Chemical Shifts: Density Functional Theory Molecular Dynamics Study of PtII and PtIV Anionic Complexes in Aqueous Solution. J Am Chem Soc 2010; 132:3472-83. [DOI: 10.1021/ja9096863] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lionel A. Truflandier
- Department of Chemistry, 312 Natural Sciences Complex, State University of New York, Buffalo, New York 14260-3000
| | - Jochen Autschbach
- Department of Chemistry, 312 Natural Sciences Complex, State University of New York, Buffalo, New York 14260-3000
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17
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Geometrical Structures of the First Solvation Shell of the [PdCl 4] 2Core: Charge-Dipole vs Dipole-Dipole Interaction of ((Pd II}...Solvent). B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.11.2295] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Geometrical Characteristics and Reactivities of Tetracoordinated Pd Complexes: Mono- and Bidentate Ligands and Charged and Uncharged Ligands. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.3.627] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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19
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Ozimiński WP, Garnuszek P, Bednarek E, Dobrowolski JC. The platinum complexes with histamine: Pt(II)(Hist)Cl2, Pt(II)(Iodo-Hist)Cl2 and Pt(IV)(Hist)2Cl2. Inorganica Chim Acta 2007. [DOI: 10.1016/j.ica.2006.10.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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20
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Kramer J, Koch KR. 195Pt NMR Study of the Speciation and Preferential Extraction of Pt(IV)−Mixed Halide Complexes by Diethylenetriamine-Modified Silica-Based Anion Exchangers. Inorg Chem 2006; 45:7843-55. [PMID: 16961377 DOI: 10.1021/ic0609655] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A detailed 195Pt NMR study of the distribution of Pt(IV) complex species resulting from the aquation of H2PtCl6, H2PtBr6, and mixtures of H2PtCl6/H2PtBr6 in water/dilute HClO4 has been carried out to obtain an understanding of the speciation in these solutions as relevant to the recovery of Pt(IV) complexes from process solutions. A species distribution plot of the [PtCl6]2-, [PtCl5(H2O)]-, and [PtCl4(H2O)2] shows that in equilibrated, relatively concentrated H2PtCl6 solutions ([Pt]t > 0.12 M), the [PtCl4(H2O)2] species is below the 195Pt NMR detection limit; for [Pt]t concentrations < 0.1 M, the relative concentrations of the [PtCl5(H2O)]- and [PtCl4(H2O)2] species increase significantly, as a result of relatively rapid aquation of the [PtCl6]2- and [PtCl5(H2O)]- complexes under these conditions. From this (195)Pt NMR data the aquation constants of [PtCl6]2- and [PtBr6]2- of log K6 approximately 1.75 +/- 0.05 and log K6 approximately 2.71 +/- 0.15, respectively, have been determined at 30 degrees C. In mixtures of H2PtCl6/H2PtBr6 in water, a number of previously unidentified aquated complexes of the general formula [PtCl(5-n)Br(n)(H2O)]- (n = 0-5) could be identified, including the possible geometrical isomers of these complexes. These 195Pt NMR assignments were confirmed by remarkably systematic, linear relationships between the 195Pt chemical shift increments induced by substitution of Cl- ions by n Br- ions in [PtCl(6-n)Br(n)]2- and [PtCl(5-n)Br(n)(H2O)]- complexes. Preferential extraction of the [PtX6]2- (X = Cl, Br, or a mixture of the two halides) species over their corresponding aquated [PtX5(H2O)]- counterparts by silica-based diethylenetriamine anion exchangers could be demonstrated by means of 195Pt NMR spectroscopy.
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Affiliation(s)
- Jurjen Kramer
- Department of Chemistry and Polymer Science, University of Stellenbosch, Private Bag X1, Matieland, 7602 Stellenbosch, South Africa
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21
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Lopes JF, de A Menezes VS, Duarte HA, Rocha WR, De Almeida WB, Dos Santos HF. Monte Carlo Simulation of Cisplatin Molecule in Aqueous Solution. J Phys Chem B 2006; 110:12047-54. [PMID: 16800515 DOI: 10.1021/jp057448c] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The Lennard-Jones (12-6) parameters were obtained for all atoms of cisplatin molecule using the ab initio quantum mechanical potential energy surface for the water-cisplatin interaction as reference data. The parameters found were (epsilon/kcal.mol(-1) and sigma/angstroms) 1.0550, 3.6590 (Pt); 0.0381, 4.6272 (Cl); 0.0455, 3.3783 (N); and 0.0185, 0.0936 (H) and provided very good results for the description of the aqueous solution of cisplatin through Monte Carlo simulation. From statistical analysis of solute-solvent interactions, we observed that the NH3 groups are involved in 53% of the calculated hydrogen bonds with a significant contribution from chlorides (41%) and only 6% involving the Pt center. This is in agreement with the expected behavior for such molecules. Two hydration shells with 22 and 81 water molecules, respectively, centered around 4.6 and 7.3 angstroms were found from the center of mass pair correlation function analysis. The cisplatin atomic Lennard-Jones parameters are reported for the first time, and they might be useful for studying the structure, properties, and processes of cisplatin-like molecules in aqueous solution, including explicitly the solvent effect.
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Affiliation(s)
- Juliana Fedoce Lopes
- NEQC: Núcleo de Estudos em Química Computacional, Departamento de Química, ICE, Universidade Federal de Juiz de Fora, Campus Martelos, CEP 36036-900, Juiz de Fora, MG, Brazil
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22
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Sterzel M, Autschbach J. Toward an Accurate Determination of 195Pt Chemical Shifts by Density Functional Computations: The Importance of Unspecific Solvent Effects and the Dependence of Pt Magnetic Shielding Constants on Structural Parameters. Inorg Chem 2006; 45:3316-24. [PMID: 16602791 DOI: 10.1021/ic052143y] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Density functional theory using the zero-order regular approximate two-component relativistic Hamiltonian has been applied to calculate the 195Pt chemical shifts for the complexes [PtCl6]2-, [PtCl4]2-, and [Pt2(NH3)2Cl2((CH3)3CCONH)2(CH2COCH3)]Cl. It is demonstrated that, in contrast to recent findings by other authors, platinum chemical shift calculations require not only a basis set beyond polarized triple-zeta quality for the metal atom but also, in principle, the consideration of explicit solvent molecules in addition to a continuum model for the first two complexes. We find that the inclusion of direct solvent-solute interactions at the quantum mechanical level is important for obtaining reasonable results despite that fact that these solvent effects are rather nonspecific. The importance of solvent effects has also implications on how experimental data should be interpreted. Further, in contrast to several previous studies of heavy-metal NMR parameters, functionals beyond the local density approximation were required both in the geometry optimization and the NMR calculations to obtain reasonable agreement between the computed and experimental NMR data. This comes with the disadvantage, however, of increased Pt-ligand bond distances leading to less good agreement with experiment for structural data. A detailed analysis of the results for the two chloroplatinate complexes is presented. The same computational procedure has then been applied to the dinuclear Pt(III) complex. Chemical shifts have been calculated with respect to both [PtCl6]2- and [PtCl4]2- chosen as the NMR reference, yielding good agreement with experiment. The determination of preferred solvent locations around the complexes studied turned out to be important for reproducing experimental data.
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Affiliation(s)
- Mariusz Sterzel
- Department of Chemistry, State University of New York at Buffalo, Buffalo, New York 14260-3000, USA
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Koch KR, Burger MR, Kramer J, Westra AN. 195Pt NMR and DFT computational methods as tools towards the understanding of speciation and hydration/solvation of [PtX6]2−(X = Cl−, Br−) anions in solution. Dalton Trans 2006:3277-84. [PMID: 16820837 DOI: 10.1039/b605182k] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
195Pt NMR together with DFT calculations and MD simulations, offer a powerful toolkit with which to probe the hydration shells of the [PtCl6]2- anions, which may lead to a more profound understanding of the solute-solvent interactions of such complexes.
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Affiliation(s)
- Klaus R Koch
- Department of Chemistry and Polymer Science, University of Stellenbosch, P. Bag X1, Matieland, 7602, South Africa.
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Potential Energy Curves and Geometrical Structure Variations for ([MX4]2-: M=Ni(II), Pd(II), Pt(II); X=Cl-, Br-) Dissociating into ([MX3]-+X-) : Ab Initio Study. B KOREAN CHEM SOC 2005. [DOI: 10.5012/bkcs.2005.26.11.1795] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Naidoo KJ, Lopis AS, Westra AN, Robinson DJ, Koch KR. Contact Ion Pair between Na+ and PtCl62- Favored in Methanol. J Am Chem Soc 2003; 125:13330-1. [PMID: 14583008 DOI: 10.1021/ja035326x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ion-pair formation between a Na+ cation and the [PtCl62-] anion in methanol is observed from195Pt NMR chemical shift trends as well as from molecular dynamics computer simulations. Free energy of association calculations reveal that contact ion pairs (CIPs) are the most favored configuration in methanol, followed by solvent shared ion pairs (SSHIPs). By contrast, such ion-pair formation is not observed for comparable solutions in water.
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Affiliation(s)
- Kevin J Naidoo
- Department of Chemistry, University of Cape Town, Rondebosch, 7701, South Africa.
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Naidoo KJ, Klatt G, Koch KR, Robinson DJ. Geometric hydration shells for anionic platinum group metal chloro complexes. Inorg Chem 2002; 41:1845-9. [PMID: 11925178 DOI: 10.1021/ic010719n] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Solvation shells surrounding complex inorganic anions have not been extensively studied and are often mentioned with an amorphous picture in mind. We use a computational model previously validated against experimental results and ab initio quantum calculations (Lienke, A.; Klatt, G.; Robinson, D.; Koch, K. R.; Naidoo, K. J. Inorg.Chem. 2001, 40, 2352-2357) to investigate the nature of the hydration shells about simple platinum group metal chloro complexes ([PtCl(6)](2-), [RhCl(6)](3-), [PtCl(4)](2-), and [PdCl(4)](2-)). Our simulations show that the hydration shells surrounding these complexes are symmetric and take on familiar geometric forms. We find that only the [RhCl(6)](3-) complex has a clearly defined second hydration shell while the [PtCl(6)](2-), [PtCl(4)](2-), and [PdCl(4)](2-) second hydration shells are more diffuse.
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Affiliation(s)
- Kevin J Naidoo
- Departments of Chemistry, University of Cape Town, Rondebosch 7701, South Africa.
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