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Bian J, Duran J, Shin WG, Ramos-Méndez J, Sankey JC, Childress L, Seuntjens J, Enger SA. GEANT4-DNA simulation of temperature-dependent and pH-dependent yields of chemical radiolytic species. Phys Med Biol 2023; 68:124002. [PMID: 37230081 DOI: 10.1088/1361-6560/acd90d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 05/25/2023] [Indexed: 05/27/2023]
Abstract
Objective.GEANT4-DNA can simulate radiation chemical yield (G-value) for radiolytic species such as the hydrated electron (eaq-) with the independent reaction times (IRT) method, however, only at room temperature and neutral pH. This work aims to modify the GEANT4-DNA source code to enable the calculation ofG-values for radiolytic species at different temperatures and pH values.Approach.In the GEANT4-DNA source code, values of chemical parameters such as reaction rate constant, diffusion coefficient, Onsager radius, and water density were replaced by corresponding temperature-dependent polynomials. The initial concentration of hydrogen ion (H+)/hydronium ion (H3O+) was scaled for a desired pH using the relationship pH = -log10[H+]. To validate our modifications, two sets of simulations were performed. (A) A water cube with 1.0 km sides and a pH of 7 was irradiated with an isotropic electron source of 1 MeV. The end time was 1μs. The temperatures varied from 25 °C to 150 °C. (B) The same setup as (A) was used, however, the temperature was set to 25 °C while the pH varied from 5 to 9. The results were compared with published experimental and simulated work.Main results.The IRT method in GEANT4-DNA was successfully modified to simulateG-values for radiolytic species at different temperatures and pH values. Our temperature-dependent results agreed with experimental data within 0.64%-9.79%, and with simulated data within 3.52%-12.47%. The pH-dependent results agreed well with experimental data within 0.52% to 3.19% except at a pH of 5 (15.99%) and with simulated data within 4.40%-5.53%. The uncertainties were below ±0.20%. Overall our results agreed better with experimental than simulation data.Significance.Modifications in the GEANT4-DNA code enabled the calculation ofG-values for radiolytic species at different temperatures and pH values.
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Affiliation(s)
- Jingyi Bian
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Juan Duran
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Wook-Geun Shin
- Physics Division, Department of Radiation Oncology, Massachusetts General Hospital & Harvard Medical School, Boston, MA-02114, United States of America
| | - Jose Ramos-Méndez
- Department of Radiation Oncology, University of California San Francisco, CA, United States of America
| | - Jack C Sankey
- Department of Physics, McGill University, Montreal, Quebec, Canada
| | - Lilian Childress
- Department of Physics, McGill University, Montreal, Quebec, Canada
| | - Jan Seuntjens
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
| | - Shirin A Enger
- Medical Physics Unit, Department of Oncology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
- Research Institute of the McGill University Health Centre, Montreal, Quebec, Canada
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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Ndongo Assomo JGG, Ebrahimi S, Muroya Y, Jay-Gerin JP, Soldera A. Molecular Dynamics Simulation Reveals a Change in the Structure of Liquid Water Near 150 °C, which May Explain Apparent Anomalies in High-Temperature Water Radiolysis. CHEMISTRY AFRICA 2022. [DOI: 10.1007/s42250-022-00513-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Gao L, Zhang L, Fu Q, Bu Y. Molecular Dynamics Characterization of Dielectron Hydration in Liquid Water with Unique Double Proton Transfers. J Chem Theory Comput 2021; 17:666-677. [PMID: 33474934 DOI: 10.1021/acs.jctc.0c01123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Radiation chemistry of water and aqueous solutions has always been an interesting scientific issue owing to involving electronic excitations, ionization of solvated species, and formation of radiolytic species and many elementary reactions, but the underlying mechanisms are still poorly understood. Here, we for the first time molecular dynamics characterize the hydration dynamics of two correlated electrons and their triggered unique phenomena in liquid water associated with radiolysis of water using the combined hybrid functional and nonlocal dispersion functional. Hydration of two electrons may experience two distinctly different mechanisms, one forming a spin-paired closed-shell unicaged dielectron hydrate (e22-aq) and the other forming a spin-paired metastable open-shell bicaged hydrated electron pair (e-aq···e-aq) which exhibits intriguing antiferromagnetic spin coupling dynamics (in a range of -40 cm-1 to -500 cm-1). e-aq···e-aq can recombine to e22-aq through a unique solvent fluctuation-controlled gradual-flowing mechanism, and enlarging fluctuation can promote the conversion. Interestingly, we directly observe that e22-aq as the precursor can trigger hydrogen evolution via unique continuous spontaneous double proton transfer to the dielectron with a short-lived H-aq intermediate, but e-aq···e-aq does not directly. This is the first direct observation for the connection between e22-aq and spontaneous hydrogen evolution including participation of H-aq in aqueous solution, bridging relevant experimental phenomena. This work also evidences an unnoticed process, the double proton transfer mediated charge separation, and presents the first detailed analysis regarding the evolution dynamics of e22-aq for the understanding of the radiolysis reactions in aqueous solutions.
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Affiliation(s)
- Liang Gao
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Liang Zhang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Qiang Fu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Yuxiang Bu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
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Abstract
The partial molar volume of the hydrated electron was investigated with pulse radiolysis and transient absorption by measuring the pressure dependence of the equilibrium constant for e-aq + NH4+ ⇔ H + NH3. At 2 kbar pressure, the equilibrium constant decreases relative to 1 bar by only 6%. Using tabulated molar volumes for ammonia and ammonium, we have the result V̅(e-aq) - V̅(H) = 11.3 cm3/mol at 25 °C, confirming that V̅(e-aq) is positive and even larger than the hydrophobic H atom. Assuming on the basis of recent molecular dynamics simulations that the molar volume of the H atom is somewhat less than that of H2, we estimate V̅(e-aq) = 26 ± 6 cm3/mol. The positive molar volume is consistent with an electron that exists largely in a small solvent void (cavity), ruling out a recent model ( Larsen , R. E. ; Glover , W. J. ; Schwartz , B. J. Science 2010 , 329 , 65 - 69 ) that suggests a noncavity structure with negative molar volume.
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Affiliation(s)
- Ireneusz Janik
- Radiation Laboratory , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - Alexandra Lisovskaya
- Radiation Laboratory , University of Notre Dame , Notre Dame , Indiana 46556 , United States
| | - David M Bartels
- Radiation Laboratory , University of Notre Dame , Notre Dame , Indiana 46556 , United States
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Patwary MM, Kanike V, Sanguanmith S, Meesungnoen J, Islam MM, Jay-Gerin JP. Low linear energy transfer radiolysis of supercritical water at 400 °C: in situ generation of ultrafast, transient, density-dependent "acid spikes". Phys Chem Chem Phys 2019; 21:7137-7146. [PMID: 30888004 DOI: 10.1039/c9cp00790c] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
There is growing interest in the radiation chemistry of supercritical water (SCW), as its use as a coolant in a nuclear reactor (Generation IV) is the logical evolution of the current (Generation III or less) water-cooled reactors. However, current knowledge about the potential effects of water radiolysis in a Gen-IV supercritical water-cooled reactor (SCWR) is incomplete. In this work, Monte Carlo track chemistry simulations of the low linear energy transfer (LET) radiolysis of SCW (H2O) at 400 °C are used in combination with a spherical "spur" model to study the effect of water density on the in situ radiolytic formation of H3O+ ions and the corresponding abrupt, transient, highly acidic pH response ("acid spikes") that is observed immediately after irradiation. The magnitude and duration of this acidic pH effect depend on the water density in the considered range of 0.15-0.6 g cm-3. It is strongest at times less than a few tens of picoseconds with the pH remaining nearly constant at ∼1.6 and 1.9 for the highest ("liquid-like") and lowest ("gas-like") density, respectively. At longer times, the pH gradually increases for all densities and finally reaches a constant value corresponding to the non-radiolytic, pre-irradiation concentration of H3O+, due to the autoprotolysis of water. Our results show that the lower the density of the water, the longer the time required to reach this constant value, ranging from ∼50 ns at 0.6 g cm-3 (pH ∼ 5.6) to ∼1 μs at 0.15 g cm-3 (pH ∼ 8.5). The generation of these highly acidic pH fluctuations around the "native" radiation tracks, though local and transient, raises questions about the potential implications of this effect in proposed Gen-IV SCW-cooled reactors regarding corrosion and degradation of materials.
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Affiliation(s)
- Md Mohsin Patwary
- Département de Médecine Nucléaire et de Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, Québec J1H 5N4, Canada.
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6
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Belmouaddine H, Shi M, Sanche L, Houde D. Tuning the size of gold nanoparticles produced by multiple filamentation of femtosecond laser pulses in aqueous solutions. Phys Chem Chem Phys 2018; 20:23403-23413. [PMID: 30178785 DOI: 10.1039/c8cp02054j] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In the present study, we consider the self-regulated generation of spatially homogeneous low density plasma (LDP) micro-channels as a high intensity ionization source arising from the multi-filamentation of powerful femtosecond (fs) laser pulses in aqueous solutions. We investigate the modulation of the femtosecond laser multiple filamentation for tuning the size of gold nanoparticles (AuNPs) synthesized in an irradiated gold chloride solution. Previous studies on the radiation-induced synthesis of colloidal gold by more conventional ionization sources, such as high energy γ-rays and electron beams, highlighted the dependence of the size distribution of AuNPs on the density of energy deposited per unit of time, i.e. the dose rate. The present method of laser-induced production of AuNPs rests on a similar radiation-assisted process, i.e. the reduction of the solvated trivalent gold ions by the hydrated electrons produced upon ionization of water. We find that trivial optical manipulation varies the rate of deposited energy by laser irradiation, which can be considered equivalent to a variation of the dose rate. We investigate the influence of varying the density of energy deposited on the laser-induced gold cluster size distribution and made a comparison with the high energy radiation-induced synthesis of AuNPs. Here, our results highlight that the present method of laser irradiation, in the regime of LDP generation, mimics the radiolysis of water at an adjustable high dose rate. More generally, these spatially and temporally resolved plasmas could be developed as a tool for the unprecedented control of chemistry under ionizing radiation.
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Affiliation(s)
- Hakim Belmouaddine
- Department of Nuclear Medicine and Radiobiology, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
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Liu G, Landry C, Ghandi K. Prediction of rate constants of important chemical reactions in water radiation chemistry in sub and supercritical water – non-equilibrium reactions. CAN J CHEM 2018. [DOI: 10.1139/cjc-2017-0315] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The rate constants for reactions involved in the radiolysis of water under relevant thermodynamic conditions in supercritical water-cooled reactors are estimated for inputs in simulations of the radiation chemistry in Generation IV nuclear reactors. We have discussed the mechanism of each chemical reaction with a focus on non-equilibrium reactions. We found most of the reactions are activation controlled above the critical point and that the rate constants are not significantly pressure dependent below 300 °C. This work will aid industry with developing chemical control strategies to suppress the concentration of eroding species.
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Affiliation(s)
- Guangdong Liu
- Department of Physics, Mount Allison University, Sackville, NB E4L 1E2, Canada
| | - Cody Landry
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville, NB E4L 1E2, Canada
| | - Khashayar Ghandi
- Department of Physics, Mount Allison University, Sackville, NB E4L 1E2, Canada
- Department of Chemistry and Biochemistry, Mount Allison University, Sackville, NB E4L 1E2, Canada
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8
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Swiatla-Wojcik D. Hybrid method for numerical modelling of LWR coolant chemistry. Radiat Phys Chem Oxf Engl 1993 2016. [DOI: 10.1016/j.radphyschem.2016.07.005] [Citation(s) in RCA: 3] [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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9
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Application of Radiation Chemistry to Some Selected Technological Issues Related to the Development of Nuclear Energy. Top Curr Chem (Cham) 2016; 374:60. [DOI: 10.1007/s41061-016-0058-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 07/22/2016] [Indexed: 10/21/2022]
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10
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Sterniczuk M, Yakabuskie PA, Wren JC, Jacob JA, Bartels DM. Low LET radiolysis escape yields for reducing radicals and H2 in pressurized high temperature water. Radiat Phys Chem Oxf Engl 1993 2016. [DOI: 10.1016/j.radphyschem.2015.12.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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11
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Sanguanmith S, Meesungnoen J, Guzonas DA, Stuart CR, Jay-Gerin JP. Radiolysis of Supercritical Water at 400°C: A Sensitivity Study of the Density Dependence of the Yield of Hydrated Electrons on the (eaq−+eaq−) Reaction Rate Constant. JOURNAL OF NUCLEAR ENGINEERING AND RADIATION SCIENCE 2016. [DOI: 10.1115/1.4031013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The temperature dependence of the rate constant (k) of the bimolecular reaction of two hydrated electrons (eaq−) measured in alkaline water exhibits an abrupt drop between 150°C and 200°C; above 250°C, it is too small to be measured reliably. Although this result is well established, the applicability of this sudden drop in k(eaq−+eaq−)) above ∼150°C to neutral or slightly acidic solution, as recommended by some authors, still remains uncertain. In fact, the recent work suggested that in near-neutral water the abrupt change in k above ∼150°C does not occur and that k should increase, rather than decrease, at temperatures greater than 150°C with roughly the same Arrhenius dependence of the data below 150°C. In view of this uncertainty of k, Monte Carlo simulations were used in this study to examine the sensitivity of the density dependence of the yield of eaq− in the low–linear energy transfer (LET) radiolysis of supercritical water (H2O) at 400°C on variations in the temperature dependence of k. Two different values of the eaq− self-reaction rate constant at 400°C were used: one was based on the temperature dependence of k above 150°C as measured in alkaline water (4.2×108 M−1 s−1), and the other was based on an Arrhenius extrapolation of the values below 150°C (2.5×1011 M−1 s−1). In both cases, the density dependences of our calculated eaq− yields at ∼60 ps and 1 ns were found to compare fairly well with the available picosecond pulse radiolysis experimental data (for D2O) for the entire water density range studied (∼0.15–0.6 g/cm3). Only a small effect of k on the variation of G(eaq−)) as a function of density at 60 ps and 1 ns could be observed. In conclusion, our present calculations did not allow us to unambiguously confirm (or deny) the applicability of the predicted sudden drop of k(eaq−+eaq−) at ∼150°C in near-neutral water.
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Affiliation(s)
- Sunuchakan Sanguanmith
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada e-mail:
| | - Jintana Meesungnoen
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada e-mail:
| | - David A. Guzonas
- Canadian Nuclear Laboratories, Reactor Chemistry and Corrosion, 20 Forest Avenue, Deep River, ON K0J 1P0, Canada e-mail:
| | - Craig R. Stuart
- Canadian Nuclear Laboratories, Reactor Chemistry and Corrosion, 20 Forest Avenue, Deep River, ON K0J 1P0, Canada e-mail:
| | - Jean-Paul Jay-Gerin
- Department of Nuclear Medicine and Radiobiology, Université de Sherbrooke, 3001, 12e Avenue Nord, Sherbrooke, QC J1H 5N4, Canada e-mail:
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12
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Swiatla-Wojcik D. Water-structure based mechanistic view on the bimolecular decay of the hydrated electron. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.10.046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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13
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Meesungnoen J, Sanguanmith S, Jay-Gerin JP. Yields of H2 and hydrated electrons in low-LET radiolysis of water determined by Monte Carlo track chemistry simulations using phenol/N2O aqueous solutions up to 350 °C. RSC Adv 2015. [DOI: 10.1039/c5ra15801j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The effect of temperature on the yields of H2 and hydrated electrons in the low linear energy transfer radiolysis of water has been modeled by Monte Carlo track chemistry simulations using phenol/N2O aqueous solutions from 25 up to 350 °C.
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Affiliation(s)
- Jintana Meesungnoen
- Département de Médecine Nucléaire et Radiobiologie
- Faculté de Médecine et des Sciences de la Santé
- Université de Sherbrooke
- Sherbrooke
- Canada
| | - Sunuchakan Sanguanmith
- Département de Médecine Nucléaire et Radiobiologie
- Faculté de Médecine et des Sciences de la Santé
- Université de Sherbrooke
- Sherbrooke
- Canada
| | - Jean-Paul Jay-Gerin
- Département de Médecine Nucléaire et Radiobiologie
- Faculté de Médecine et des Sciences de la Santé
- Université de Sherbrooke
- Sherbrooke
- Canada
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Butarbutar SL, Meesungnoen J, Guzonas DA, Stuart CR, Jay-Gerin JP. Modeling the Radiolysis of Supercritical Water by Fast Neutrons: Density Dependence of the Yields of Primary Species at 400°C. Radiat Res 2014; 182:695-704. [DOI: 10.1667/rr13715.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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15
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Sanguanmith S, Meesungnoen J, Jay-Gerin JP. Time-dependent yield of OH radicals in the low linear energy transfer radiolysis of water between 25 and 350 °C. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.09.057] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Meesungnoen J, Sanguanmith S, Jay-Gerin JP. Density dependence of the yield of hydrated electrons in the low-LET radiolysis of supercritical water at 400 °C: influence of the geminate recombination of subexcitation-energy electrons prior to thermalization. Phys Chem Chem Phys 2013; 15:16450-5. [DOI: 10.1039/c3cp52630e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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18
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Kanjana K, Haygarth KS, Wu W, Bartels DM. Laboratory studies in search of the critical hydrogen concentration. Radiat Phys Chem Oxf Engl 1993 2013. [DOI: 10.1016/j.radphyschem.2012.09.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Sanguanmith S, Meesungnoen J, Muroya Y, Lin M, Katsumura Y, Jay-Gerin JP. On the spur lifetime and its temperature dependence in the low linear energy transfer radiolysis of water. Phys Chem Chem Phys 2012; 14:16731-6. [PMID: 23138332 DOI: 10.1039/c2cp42826a] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the spirit of the radiation chemical "spur model", the lifetime of a spur (τ(s)) is an important indicator of overlapping spurs and the establishment of homogeneity in the distribution of reactive species created by the action of low linear energy transfer (LET) radiation (such as fast electrons or γ irradiation). In fact, τ(s) gives the time required for the changeover from nonhomogeneous spur kinetics to homogeneous kinetics in the bulk solution, thus defining the so-called primary (or "escape") radical and molecular yields of radiolysis, which are obviously basic to the quantitative understanding of any irradiated chemical system. In this work, τ(s) and its temperature dependence have been determined for the low-LET radiolysis of deaerated 0.4 M aqueous solutions of H(2)SO(4) and pure liquid water up to 350 °C using a simple model of energy deposition initially in spurs, followed by random diffusion of the species of the spur during track expansion until spur overlap is complete. Unlike our previous τ(s) calculations, based on irradiated Fricke dosimeter simulations, the current model is free from any effects due to the presence of oxygen or the use of scavengers. In acidic solutions, the spur lifetime values thus obtained are in very good agreement with our previous calculations (after making appropriate corrections, however, to account for the possibility of competition between oxygen and Fe(2+) ions for H˙ atoms in the Fricke dosimeter, an effect which was not included in our original simulations). In this way, we confirm the validity of our previous approach. As expected, in the case of pure, oxygen-free water, our calculated times required to reach complete spur overlap are essentially the same (within uncertainty limits) as those found in acidic solutions. This explicitly reflects the fact that the diffusion coefficients for the hydrated electron and the H˙ atom that are involved in the overall calculation of the lifetime of spurs in neutral or acidic media, respectively, are of similar magnitude over the 25-350 °C temperature range studied.
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Affiliation(s)
- Sunuchakan Sanguanmith
- Département de Médecine Nucléaire et Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, 3001, 12ème Avenue Nord, Sherbrooke (Québec) J1H 5N4, Canada
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20
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Osawa K, Terazima M, Kimura Y. Electron Transfer Reaction Dynamics of p-Nitroaniline in Water from Liquid to Supercritical Conditions. J Phys Chem B 2012; 116:11508-16. [DOI: 10.1021/jp305970r] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Koji Osawa
- Department of Chemistry, Graduate School
of Science, Kyoto University, Kyoto 606-8502,
Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School
of Science, Kyoto University, Kyoto 606-8502,
Japan
| | - Yoshifumi Kimura
- Department of Chemistry, Graduate School
of Science, Kyoto University, Kyoto 606-8502,
Japan
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21
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Stähler J, Gahl C, Wolf M. Dynamics and reactivity of trapped electrons on supported ice crystallites. Acc Chem Res 2012; 45:131-8. [PMID: 22185698 DOI: 10.1021/ar200170s] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The solvation dynamics and reactivity of localized excess electrons in aqueous environments have attracted great attention in many areas of physics, chemistry, and biology. This manifold attraction results from the importance of water as a solvent in nature as well as from the key role of low-energy electrons in many chemical reactions. One prominent example is the electron-induced dissociation of chlorofluorocarbons (CFCs). Low-energy electrons are also critical in the radiation chemistry that occurs in nuclear reactors. Excess electrons in an aqueous environment are localized and stabilized by the local rearrangement of the surrounding water dipoles. Such solvated or hydrated electrons are known to play an important role in systems such as biochemical reactions and atmospheric chemistry. Despite numerous studies over many years, little is known about the microscopic details of these electron-induced chemical processes, and interest in the fundamental processes involved in the reactivity of trapped electrons continues. In this Account, we present a surface science study of the dynamics and reactivity of such localized low-energy electrons at D(2)O crystallites that are supported by a Ru(001) single crystal metal surface. This approach enables us to investigate the generation and relaxation dynamics as well as dissociative electron attachment (DEA) reaction of excess electrons under well-defined conditions. They are generated by photoexcitation in the metal template and transferred to trapping sites at the vacuum interface of crystalline D(2)O islands. In these traps, the electrons are effectively decoupled from the electronic states of the metal template, leading to extraordinarily long excited state lifetimes on the order of minutes. Using these long-lived, low-energy electrons, we study the DEA to CFCl(3) that is coadsorbed at very low concentrations (∼10(12) cm(-2)). Using rate equations and direct measurement of the change of surface dipole moment, we estimated the electron surface density for DEA, yielding cross sections that are orders of magnitude higher than the electron density measured in the gas phase.
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Affiliation(s)
- Julia Stähler
- Department of Physical Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Cornelius Gahl
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
- Max-Born-Institute Berlin, Max-Born-Str. 2 A, 12489 Berlin, Germany
| | - Martin Wolf
- Department of Physical Chemistry, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
- Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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Muroya Y, Sanguanmith S, Meesungnoen J, Lin M, Yan Y, Katsumura Y, Jay-Gerin JP. Time-dependent yield of the hydrated electron in subcritical and supercritical water studied by ultrafast pulse radiolysis and Monte-Carlo simulation. Phys Chem Chem Phys 2012; 14:14325-33. [DOI: 10.1039/c2cp42260c] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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23
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Sanguanmith S, Meesungnoen J, Jay-Gerin JP. Density dependence of the “escape” yield of hydrated electrons in the low-LET radiolysis of supercritical water at 400 °C. Phys Chem Chem Phys 2012; 14:11277-80. [DOI: 10.1039/c2cp41399j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Low-linear energy transfer radiolysis of liquid water at elevated temperatures up to 350°C: Monte-Carlo simulations. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.04.059] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Stähler J, Meyer M, Bovensiepen U, Wolf M. Solvation dynamics of surface-trapped electrons at NH3 and D2O crystallites adsorbed on metals: from femtosecond to minute timescales. Chem Sci 2011. [DOI: 10.1039/c0sc00644k] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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Sanguanmith S, Muroya Y, Tippayamontri T, Meesungnoen J, Lin M, Katsumura Y, Jay-Gerin JP. Temperature dependence of the Fricke dosimeter and spur expansion time in the low-LET high-temperature radiolysis of water up to 350 °C: a Monte-Carlo simulation study. Phys Chem Chem Phys 2011; 13:10690-8. [DOI: 10.1039/c1cp20293f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Meesungnoen J, Guzonas D, Jay-Gerin JP. Radiolysis of supercritical water at 400 °C and liquid-like densities near 0.5 g/cm3 — A Monte Carlo calculation. CAN J CHEM 2010. [DOI: 10.1139/v10-055] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Monte Carlo simulations are used to calculate the primary radical yields [Formula: see text], g(•OH), the sum [[Formula: see text] + g(•OH) + g(H•)], and the ratio g(H•)/[Formula: see text] in the low linear energy transfer (LET) radiolysis of supercritical water (SCW) at 400 °C in the high-density, liquid-like region near ∼0.5 g/cm3. Using all the currently available information on the reactivities and diffusion coefficients of the radiation-induced species under these conditions, and assuming the aqueous medium to be a “continuum”, a good accord is found between our calculations and the available experimental data. In particular, our computed [Formula: see text] yields at 60 ps and 1 ns compare very well with recently reported direct time-dependent [Formula: see text] yield measurements in SCW (D2O) at 400 °C and 0.570 g/cm3 using picosecond pulse radiolysis experiments.
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Affiliation(s)
- Jintana Meesungnoen
- Département de Médecine Nucléaire et de Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
- Reactor Chemistry and Corrosion Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON K0J 1J0, Canada
| | - David Guzonas
- Département de Médecine Nucléaire et de Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
- Reactor Chemistry and Corrosion Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON K0J 1J0, Canada
| | - Jean-Paul Jay-Gerin
- Département de Médecine Nucléaire et de Radiobiologie, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
- Reactor Chemistry and Corrosion Branch, Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON K0J 1J0, Canada
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Haygarth KS, Marin TW, Janik I, Kanjana K, Stanisky CM, Bartels DM. Carbonate radical formation in radiolysis of sodium carbonate and bicarbonate solutions up to 250 degrees C and the mechanism of its second order decay. J Phys Chem A 2010; 114:2142-50. [PMID: 20078055 DOI: 10.1021/jp9105162] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Pulse radiolysis experiments published several years ago (J. Phys. Chem. A, 2002, 106, 2430) raised the possibility that the carbonate radical formed from reaction of *OH radicals with either HCO(3)(-) or CO(3)(2-) might actually exist predominantly as a dimer form, for example, *(CO(3))(2)(3-). In this work we re-examine the data upon which this suggestion was based and find that the original data analysis is flawed. A major omission of the original analysis is the recombination reaction *OH + *CO(3)(-) --> HOOCO(2)(-). Upon reanalysis of the published data for sodium bicarbonate solutions and analysis of new transient absorption data we are able to establish the rate constant for this reaction up to 250 degrees C. The mechanism for the second-order self-recombination of the carbonate radical has never been convincingly demonstrated. From a combination of literature data and new transient absorption experiments in the 1-400 ms regime, we are able to show that the mechanism involves pre-equilibrium formation of a C(2)O(6)(2-) dimer, which dissociates to CO(2) and peroxymonocarbonate anion: *CO3(-)+*CO3(-)<-->C2O6(2-)-->CO2+O2COO(2-) *CO3(-) reacts with the product peroxymonocarbonate anion, producing a peroxymonocarbonate radical *O2COO(-), which can also recombine with the carbonate radical: *CO3(-)+CO4(2-)-->*CO4(-)+CO3(2-) *CO3(-)+CO4(-)-->C2O7(2-).
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Affiliation(s)
- Kyle S Haygarth
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556, USA
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Hare PM, Price EA, Stanisky CM, Janik I, Bartels DM. Solvated Electron Extinction Coefficient and Oscillator Strength in High Temperature Water. J Phys Chem A 2010; 114:1766-75. [DOI: 10.1021/jp909789b] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Patrick M. Hare
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | - Erica A. Price
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | | | - Ireneusz Janik
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
| | - David M. Bartels
- Radiation Laboratory, University of Notre Dame, Notre Dame, Indiana 46556
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Musat R, Vigneron G, Garzella D, LeCaër S, Hergott JF, Renault JP, Pommeret S. Water reduction by photoexcited silica and alumina. Chem Commun (Camb) 2010; 46:2394-6. [DOI: 10.1039/b921231k] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Tay KA, Boutin A. Hydrated Electron Diffusion: The Importance of Hydrogen-Bond Dynamics. J Phys Chem B 2009; 113:11943-9. [DOI: 10.1021/jp810538f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Kafui A. Tay
- Laboratoire de Chimie Physique, Université de Paris-Sud XI, 91405 Orsay Cedex, France
| | - Anne Boutin
- Laboratoire de Chimie Physique, Université de Paris-Sud XI, 91405 Orsay Cedex, France
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Swiatla-Wojcik D. Modelling spur chemistry for alkaline and acidic water at high temperatures. RESEARCH ON CHEMICAL INTERMEDIATES 2009. [DOI: 10.1007/s11164-009-0053-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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