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Wang C, Zhang J, Guo W, Liu R, Yao Y. Detonation performance and shock sensitivity of energetic material NTO with embedded small molecules: a deep neural network potential accelerated molecular dynamics study. Phys Chem Chem Phys 2024. [PMID: 39328184 DOI: 10.1039/d4cp02399d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2024]
Abstract
Accurate description of detonation performance for explosives remains a challenge for current experimental and theoretical methodologies. Herein, we address this issue through combining a multi-scale shock technique and a first-principles based deep neural network potential. This approach enables us to conduct molecular dynamics simulations encompassing over a thousand atoms and extending for several nanoseconds, allowing us to evaluate the detonation performance of the insensitive explosive NTO crystal. Utilizing the ZND model, we successfully determine the detonation velocity (7.9 km s-1), and detonation pressure (33 GPa) of the NTO crystals at the C-J state, which align well with experimental results. Additionally, we predict the detonation performance of three host-guest materials: NTO/H2O2, NTO/CO2, and NTO/N2O, all of which exhibit higher detonation temperatures compared to the NTO crystals in the present model. Moreover, we proposed the time to reach the C-J state as a shock sensitivity descriptor for explosives. Our findings reveal that the order of shock sensitivity for these materials is NTO/H2O2 > NTO/N2O > NTO/CO2 > NTO, and the trend can be explained in terms of bulk modulus, electronic band gap and oxygen balance. The enhanced shock sensitivity by embedded small molecules arises not only from the reduction in initial reaction barriers, but also from the faster evolution rate of final products and the release of more heat. Our research might present a cutting-edge framework for precisely, quickly, and safely evaluating and modulating the detonation performance and shock sensitivity of explosives.
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Affiliation(s)
- Caimu Wang
- Frontiers Science Center for High Energy Material (MOE), Beijing Institute of Technology, Beijing 100081, China.
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Jidong Zhang
- Department of Physics, College of Science, Shihezi University, Shihezi 832003, China
| | - Wei Guo
- Frontiers Science Center for High Energy Material (MOE), Beijing Institute of Technology, Beijing 100081, China.
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Ruibin Liu
- Frontiers Science Center for High Energy Material (MOE), Beijing Institute of Technology, Beijing 100081, China.
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
| | - Yugui Yao
- Frontiers Science Center for High Energy Material (MOE), Beijing Institute of Technology, Beijing 100081, China.
- Centre for Quantum Physics, Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurement (MOE), School of Physics, Beijing Institute of Technology, Beijing 100081, China
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Willman JT, Perriot R, Ticknor C. Atomic cluster expansion potential for large scale simulations of hydrocarbons under shock compression. J Chem Phys 2024; 161:064303. [PMID: 39120033 DOI: 10.1063/5.0213560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Accepted: 07/22/2024] [Indexed: 08/10/2024] Open
Abstract
We present an Atomic Cluster Expansion (ACE) machine learned potential developed for high-fidelity atomistic simulations of hydrocarbons, targeting pressures and temperatures near and above supercritical fluid regimes for molecular fluids. A diverse set of stoichiometries were covered in training, including 1:0 (pure carbon), 1:4 (methane), and 1:1 (benzene), and rich bonding environments sampled at supercritical temperatures, hydrogen rich, reactive mixtures where metastable stoichiometries arise, including 1:2 (ethylene) and 1:3 (ethane). A high-fidelity training database was constructed by performing large-scale quantum molecular dynamic simulations [density functional theory (DFT) MD] of diamond, graphite, methane, and benzene. A novel approach to selecting structures from DFT MD is also presented, which allows for the rapid selection of unique DFT MD frames from complex trajectories. Comparisons to DFT and experimental data demonstrate that the presented ACE potential accurately reproduces isotherms, carbon melting curves, radial distribution functions, and shock Hugoniots for carbon and hydrocarbon systems for pressures up to 100 GPa and temperatures up to 6000 K for hydrocarbon systems and up to 9000 K for pure carbon systems. This work delivers a potential that can be used for accurate, large-scale simulations of shocked hydrocarbons and demonstrates a methodology for fitting and validating machine learning interatomic potentials to complex molecular environments, which can be applied to energetic materials in future works.
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Affiliation(s)
- Jonathan T Willman
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Romain Perriot
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - Christopher Ticknor
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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3
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Lindsey RK, Bastea S, Goldman N, Fried LE. Investigating 3,4-bis(3-nitrofurazan-4-yl)furoxan detonation with a rapidly tuned density functional tight binding model. J Chem Phys 2021; 154:164115. [PMID: 33940855 DOI: 10.1063/5.0047800] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We describe a machine learning approach to rapidly tune density functional tight binding models for the description of detonation chemistry in organic molecular materials. Resulting models enable simulations on the several 10s of ps scales characteristic to these processes, with "quantum-accuracy." We use this approach to investigate early shock chemistry in 3,4-bis(3-nitrofurazan-4-yl)furoxan, a hydrogen-free energetic material known to form onion-like nanocarbon particulates following detonation. We find that the ensuing chemistry is significantly characterized by the formation of large CxNyOz species, which are likely precursors to the experimentally observed carbon condensates. Beyond utility as a means of investigating detonation chemistry, the present approach can be used to generate quantum-based reference data for the development of full machine-learned interatomic potentials capable of simulation on even greater time and length scales, i.e., for applications where characteristic time scales exceed the reach of methods including Kohn-Sham density functional theory, which are commonly used for reference data generation.
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Affiliation(s)
- Rebecca K Lindsey
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Sorin Bastea
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Laurence E Fried
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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4
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Pham CH, Lindsey RK, Fried LE, Goldman N. Calculation of the detonation state of HN3 with quantum accuracy. J Chem Phys 2020; 153:224102. [DOI: 10.1063/5.0029011] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Cong Huy Pham
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Rebecca K. Lindsey
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Laurence E. Fried
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
- Department of Chemical Engineering, University of California, Davis, California 95616, USA
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5
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Lindsey RK, Goldman N, Fried LE, Bastea S. Many-body reactive force field development for carbon condensation in C/O systems under extreme conditions. J Chem Phys 2020; 153:054103. [DOI: 10.1063/5.0012840] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Affiliation(s)
- Rebecca K. Lindsey
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
- Department of Chemical Engineering, University of California, Davis, California 95616, USA
| | - Laurence E. Fried
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
| | - Sorin Bastea
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA
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6
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Kroonblawd MP, Lindsey RK, Goldman N. Synthesis of functionalized nitrogen-containing polycyclic aromatic hydrocarbons and other prebiotic compounds in impacting glycine solutions. Chem Sci 2019; 10:6091-6098. [PMID: 31360414 PMCID: PMC6585877 DOI: 10.1039/c9sc00155g] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/19/2019] [Indexed: 01/09/2023] Open
Abstract
Proteinogenic amino acids can be produced on or delivered to a planet via impacting abiotic sources and consequently were likely present before the emergence of life on Earth. However, the role that these materials played in prebiotic scenarios remains an open question, in part because little is known about the survivability and reactivity of astrophysical organic compounds upon impact with a planetary surface. To this end, we use a force-matched semi-empirical quantum simulation method to study impacts of aqueous proteinogenic amino acids at conditions reaching 48 GPa and 3000 K. Here, we probe a relatively unstudied mechanism for prebiotic synthesis where sudden heating and pressurization causes condensation of complex carbon-rich structures from mixtures of glycine, the simplest protein-forming amino acid. These carbon-containing clusters are stable on short timescales and undergo a fundamental structural transition upon expansion and cooling from predominantly sp3-bonded tetrahedral-like moieties to those that are more sp2-bonded and planar. The recovered sp2-bonded structures include large nitrogen containing polycyclic aromatic hydrocarbons (NPAHs) with a number of different functional groups and embedded bonded regions akin to oligo-peptides. A number of small organic molecules with prebiotic relevance are also predicted to form. This work presents an alternate route to gas-phase synthesis for the formation of NPAHs of high complexity and highlights the significance of both the thermodynamic path and local chemical self-assembly in forming prebiotic species during shock synthesis. Our results help determine the role of comets and other celestial bodies in both the delivery and synthesis of potentially significant life building compounds on early Earth.
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Affiliation(s)
- Matthew P Kroonblawd
- Physical and Life Sciences Directorate , Lawrence Livermore National Laboratory , Livermore , CA 94550 , USA .
| | - Rebecca K Lindsey
- Physical and Life Sciences Directorate , Lawrence Livermore National Laboratory , Livermore , CA 94550 , USA .
| | - Nir Goldman
- Physical and Life Sciences Directorate , Lawrence Livermore National Laboratory , Livermore , CA 94550 , USA .
- Department of Chemical Engineering , University of California , Davis , California 95616 , USA
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7
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Force Matching Approaches to Extend Density Functional Theory to Large Time and Length Scales. COMPUTATIONAL APPROACHES FOR CHEMISTRY UNDER EXTREME CONDITIONS 2019. [DOI: 10.1007/978-3-030-05600-1_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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8
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Lindsey RK, Fried LE, Goldman N. Application of the ChIMES Force Field to Nonreactive Molecular Systems: Water at Ambient Conditions. J Chem Theory Comput 2018; 15:436-447. [DOI: 10.1021/acs.jctc.8b00831] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rebecca K. Lindsey
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Laurence E. Fried
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
- Department of Chemical Engineering, University of California, Davis, California 95616, United States
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9
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Bidault X, Pineau N. Dynamic formation of nanodiamond precursors from the decomposition of carbon suboxide (C 3O 2) under extreme conditions-A ReaxFF study. J Chem Phys 2018; 149:114301. [PMID: 30243287 DOI: 10.1063/1.5028456] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
We use molecular dynamics simulations with the ReaxFF-lg potential to model the high pressure pyrolysis of carbon suboxide (C3O2) in mixture with argon as a pressure bath. We show that the reactive simulations catch the experimental behavior of the low-pressure detonation of C3O2 (around 10 bars in shock tube experiments) and allow extrapolations to the high-pressure range of solid-state explosive detonation (up to 60 GPa). While at low pressure carbonaceous nanostructures are formed through the aggregation of species such as carbon dimers C2, it appears that the high pressure deeply modifies the process, with the aggregation of growing CxOy heterostructures, in which the oxygen amount is driven by the pressure and the temperature. Pressures in the order of 60 GPa lead to high oxygen ratios, which prevent carbon atoms to get four carbon neighbors (the first condition to get a diamond structure). But a pressure lowering leads to a substantial carbon enrichment through CO2/CO release and facilitates the formation of pure sp3-carbon phases where diamond precursors can form. These results give new insights on the conditions leading to nanodiamonds during the detonation of carbon-rich high explosives.
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Affiliation(s)
- X Bidault
- CEA/DAM/DIF, F-91297 Arpajon, France
| | - N Pineau
- CEA/DAM/DIF, F-91297 Arpajon, France
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10
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Koziol L, Fried LE, Goldman N. Using Force Matching To Determine Reactive Force Fields for Water under Extreme Thermodynamic Conditions. J Chem Theory Comput 2016; 13:135-146. [DOI: 10.1021/acs.jctc.6b00707] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lucas Koziol
- Physical and Life Sciences
Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Laurence E. Fried
- Physical and Life Sciences
Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Nir Goldman
- Physical and Life Sciences
Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
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11
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French M, Desjarlais MP, Redmer R. Ab initio calculation of thermodynamic potentials and entropies for superionic water. Phys Rev E 2016; 93:022140. [PMID: 26986321 DOI: 10.1103/physreve.93.022140] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Indexed: 06/05/2023]
Abstract
We construct thermodynamic potentials for two superionic phases of water [with body-centered cubic (bcc) and face-centered cubic (fcc) oxygen lattice] using a combination of density functional theory (DFT) and molecular dynamics simulations (MD). For this purpose, a generic expression for the free energy of warm dense matter is developed and parametrized with equation of state data from the DFT-MD simulations. A second central aspect is the accurate determination of the entropy, which is done using an approximate two-phase method based on the frequency spectra of the nuclear motion. The boundary between the bcc superionic phase and the ices VII and X calculated with thermodynamic potentials from DFT-MD is consistent with that directly derived from the simulations. Differences in the physical properties of the bcc and fcc superionic phases and their impact on interior modeling of water-rich giant planets are discussed.
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Affiliation(s)
- Martin French
- Universität Rostock, Institut für Physik, D-18051 Rostock, Germany
| | | | - Ronald Redmer
- Universität Rostock, Institut für Physik, D-18051 Rostock, Germany
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12
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Guo D, Zybin SV, An Q, Goddard III WA, Huang F. Prediction of the Chapman–Jouguet chemical equilibrium state in a detonation wave from first principles based reactive molecular dynamics. Phys Chem Chem Phys 2016; 18:2015-22. [DOI: 10.1039/c5cp04516a] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This Rx2CJ first principle based protocol for predicting the CJ state provides the matching point between atomistic reaction dynamic simulations and the macroscopic properties of detonation, and can be used as a measure of performance for in silico synthesis and characterization of new materials.
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Affiliation(s)
- Dezhou Guo
- State Key Laboratory of Explosion Science and Technology
- Beijing Institute of Technology
- People’s Republic of China
- Materials and Process Simulation Center
- 139-74
| | - Sergey V. Zybin
- Materials and Process Simulation Center
- 139-74
- California Institute of Technology
- Pasadena
- USA
| | - Qi An
- Materials and Process Simulation Center
- 139-74
- California Institute of Technology
- Pasadena
- USA
| | - William A. Goddard III
- Materials and Process Simulation Center
- 139-74
- California Institute of Technology
- Pasadena
- USA
| | - Fenglei Huang
- State Key Laboratory of Explosion Science and Technology
- Beijing Institute of Technology
- People’s Republic of China
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13
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Goldman N, Fried LE, Koziol L. Using Force-Matched Potentials To Improve the Accuracy of Density Functional Tight Binding for Reactive Conditions. J Chem Theory Comput 2015; 11:4530-5. [DOI: 10.1021/acs.jctc.5b00742] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nir Goldman
- Physical
and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Laurence E. Fried
- Physical
and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
| | - Lucas Koziol
- Physical
and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, United States
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14
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Goldman N. Multi-center semi-empirical quantum models for carbon under extreme thermodynamic conditions. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2014.11.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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15
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Srinivasan SG, Goldman N, Tamblyn I, Hamel S, Gaus M. A density functional tight binding model with an extended basis set and three-body repulsion for hydrogen under extreme thermodynamic conditions. J Phys Chem A 2014; 118:5520-8. [PMID: 24960065 DOI: 10.1021/jp5036713] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a new DFTB-p3b density functional tight binding model for hydrogen at extremely high pressures and temperatures, which includes a polarizable basis set (p) and a three-body environmentally dependent repulsive potential (3b). We find that use of an extended basis set is necessary under dissociated liquid conditions to account for the substantial p-orbital character of the electronic states around the Fermi energy. The repulsive energy is determined through comparison to cold curve pressures computed from density functional theory (DFT) for the hexagonal close-packed solid, as well as pressures from thermally equilibrated DFT-MD simulations of the liquid phase. In particular, we observe improved agreement in our DFTB-p3b model with previous theoretical and experimental results for the shock Hugoniot of hydrogen up to 100 GPa and 25000 K, compared to a standard DFTB model using pairwise interactions and an s-orbital basis set, only. The DFTB-p3b approach discussed here provides a general method to extend the DFTB method for a wide variety of materials over a significantly larger range of thermodynamic conditions than previously possible.
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Affiliation(s)
- Sriram Goverapet Srinivasan
- Department of Mechanical and Nuclear Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States
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16
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Goldman N, Bastea S. Nitrogen Oxides As a Chemistry Trap in Detonating Oxygen-Rich Materials. J Phys Chem A 2014; 118:2897-903. [DOI: 10.1021/jp501455z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Avenue L-288, Livermore, California 94550, United States
| | - Sorin Bastea
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, 7000 East Avenue L-288, Livermore, California 94550, United States
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17
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Bethkenhagen M, French M, Redmer R. Equation of state and phase diagram of ammonia at high pressures from ab initio simulations. J Chem Phys 2014; 138:234504. [PMID: 23802968 DOI: 10.1063/1.4810883] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
We present an equation of state as well as a phase diagram of ammonia at high pressures and high temperatures derived from ab initio molecular dynamics simulations. The predicted phases of ammonia are characterized by analyzing diffusion coefficients and structural properties. Both the phase diagram and the subsequently computed Hugoniot curves are compared to experimental results. Furthermore, we discuss two methods that allow us to take into account nuclear quantum effects, which are of considerable importance in molecular fluids. Our data cover pressures up to 330 GPa and a temperature range from 500 K to 10,000 K. This regime is of great interest for interior models of the giant planets Uranus and Neptune, which contain, besides water and methane, significant amounts of ammonia.
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18
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The Reactivity of Energetic Materials Under High Pressure and Temperature. ADVANCES IN QUANTUM CHEMISTRY 2014. [DOI: 10.1016/b978-0-12-800345-9.00006-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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19
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Qi T, Bauschlicher CW, Lawson JW, Desai TG, Reed EJ. Comparison of ReaxFF, DFTB, and DFT for Phenolic Pyrolysis. 1. Molecular Dynamics Simulations. J Phys Chem A 2013; 117:11115-25. [DOI: 10.1021/jp4081096] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tingting Qi
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Charles W. Bauschlicher
- Mail Stop 230, Entry Systems and Technology
Division, NASA Ames Research Center, Moffett Field, California 94035, United States
| | - John W. Lawson
- Mail Stop 234, Thermal Protection Materials Branch, NASA Ames Research Center, Moffett
Field, California 94035, United States
| | - Tapan G. Desai
- Advanced Cooling Technologies, Inc., Lancaster, Pennsylvania 17601, United States
| | - Evan J. Reed
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
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20
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Abstract
We present results of prebiotic organic synthesis in shock compressed mixtures of simple ices from quantum molecular dynamics (MD) simulations extended to close to equilibrium time scales. Given the likelihood of an inhospitable prebiotic atmosphere on early Earth, it is possible that impact processes of comets or other icy bodies were a source of prebiotic chemical compounds on the primitive planet. We observe that moderate shock pressures and temperatures within a CO2-rich icy mixture (36 GPa and 2800 K) produce a number of nitrogen containing heterocycles, which dissociate to form functionalized aromatic hydrocarbons upon expansion and cooling to ambient conditions. In contrast, higher shock conditions (48-60 GPa, 3700-4800 K) resulted in the synthesis of long carbon-chain molecules, CH4, and formaldehyde. All shock compression simulations at these conditions have produced significant quantities of simple C-N bonded compounds such as HCN, HNC, and HNCO upon expansion and cooling to ambient conditions. Our results elucidate a mechanism for impact synthesis of prebiotic molecules at realistic impact conditions that is independent of external constraints such as the presence of a catalyst, illuminating UV radiation, or pre-existing conditions on a planet.
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Affiliation(s)
- Nir Goldman
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory , Livermore, California 94550, United States
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21
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McGrath MJ, Kuo IFW, Ghogomu JN, Mundy CJ, Siepmann JI. Vapor–Liquid Coexistence Curves for Methanol and Methane Using Dispersion-Corrected Density Functional Theory. J Phys Chem B 2011; 115:11688-92. [DOI: 10.1021/jp205072v] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Matthew J. McGrath
- Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki, Finland
| | - I.-F. Will Kuo
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, California 94550, United States
| | - Julius N. Ghogomu
- Department of Chemistry, University of Dschang, B.P. 67, Dschang, Cameroon
- Departments of Chemistry and Chemical Engineering and Materials Science and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Christopher J. Mundy
- Chemical and Materials Sciences Division, Pacific Northwest National Laboratory, P.O. Box 999, Washington 99352, United States
| | - J. Ilja Siepmann
- Departments of Chemistry and Chemical Engineering and Materials Science and Chemical Theory Center, University of Minnesota, Minneapolis, Minnesota 55455, United States
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22
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Abstract
This review discusses new developments in shock compression science with a focus on molecular media. Some basic features of shock and detonation waves, nonlinear excitations that can produce extreme states of high temperature and high pressure, are described. Methods of generating and detecting shock waves are reviewed, especially those using tabletop lasers that can be interfaced with advanced molecular diagnostics. Newer compression methods such as shockless compression and precompression shock that generate states of cold dense molecular matter are discussed. Shock compression creates a metallic form of hydrogen, melts diamond, and makes water a superionic liquid with unique catalytic properties. Our understanding of detonations at the molecular level has improved a great deal as a result of advanced nonequilibrium molecular simulations. Experimental measurements of detailed molecular behavior behind a detonation front might be available soon using femtosecond lasers to produce nanoscale simulated detonation fronts.
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Affiliation(s)
- Dana D. Dlott
- School of Chemical Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801
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