The Experts below are selected from a list of 53760 Experts worldwide ranked by ideXlab platform
Chao Zhang - One of the best experts on this subject based on the ideXlab platform.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
Journal of Chemical Physics, 2019Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counterions from the solution to form electric double layers. In a previous work [T. Sayer et al., J. Chem. Phys 147, 104702 (2017)], we reported on a classical force field based molecular dynamics study of a prototype model system, namely, a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems [half the surface charge density for NaCl(111)]. It was demonstrated that the application of a finite macroscopic field E canceling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field D. The benefits of using D instead of E as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics, as shown in this work.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
arXiv: Chemical Physics, 2018Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counter ions from solution to form electric double layers (EDLs). In a previous work (J. Chem. Phys 147, 104702 (2017)) we reported on a classical force field based molecular dynamics study of a prototype model system namely a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems (half the surface charge density for NaCl(111)). It was demonstrated that the application of a finite macroscopic field $E$ cancelling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field $D$. The benefits of using $D$ instead of $E$ as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics (DFTMD), as shown in this work.
Thomas Sayer - One of the best experts on this subject based on the ideXlab platform.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
Journal of Chemical Physics, 2019Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counterions from the solution to form electric double layers. In a previous work [T. Sayer et al., J. Chem. Phys 147, 104702 (2017)], we reported on a classical force field based molecular dynamics study of a prototype model system, namely, a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems [half the surface charge density for NaCl(111)]. It was demonstrated that the application of a finite macroscopic field E canceling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field D. The benefits of using D instead of E as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics, as shown in this work.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
arXiv: Chemical Physics, 2018Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counter ions from solution to form electric double layers (EDLs). In a previous work (J. Chem. Phys 147, 104702 (2017)) we reported on a classical force field based molecular dynamics study of a prototype model system namely a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems (half the surface charge density for NaCl(111)). It was demonstrated that the application of a finite macroscopic field $E$ cancelling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field $D$. The benefits of using $D$ instead of $E$ as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics (DFTMD), as shown in this work.
Hui Wang - One of the best experts on this subject based on the ideXlab platform.
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high pressure partially Ionic phase of water ice
Nature Communications, 2011Co-Authors: Yanchao Wang, Hanyu Liu, Li Zhu, Hui WangAbstract:Dissociation of ice into an Ionic Solid is rare due to the high energy cost of proton transfer. In this study, structure search simulation is used to predict the formation of a partially Ionic phase in ice at low temperature and high pressure, which consists of coupled alternate layers of hydroxide and hydronium.
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high pressure partially Ionic phase of water ice
Nature Communications, 2011Co-Authors: Yanchao Wang, Hanyu Liu, Li Zhu, Hui WangAbstract:Water ice dissociates into a superIonic Solid at high temperature (>2,000 K) and pressure, where oxygen forms the lattice, but hydrogen diffuses completely. At low temperature, however, the dissociation into an Ionic ice of hydronium (H3O)+ hydroxide (OH)− is not expected because of the extremely high energy cost (∼1.5 eV) of proton transfer between H2O molecules. Here we show the pressure-induced formation of a partially Ionic phase (monoclinic P21 structure) consisting of coupled alternate layers of (OH)δ− and (H3O)δ+ (δ=0.62) in water ice predicted by particle-swarm optimization structural search at zero temperature and pressures of >14 Mbar. The occurrence of this Ionic phase follows the break-up of the typical O–H covalently bonded tetrahedrons in the hydrogen symmetric atomic phases and is originated from the volume reduction favourable for a denser structure packing. Dissociation of ice into an Ionic Solid is rare due to the high energy cost of proton transfer. In this study, structure search simulation is used to predict the formation of a partially Ionic phase in ice at low temperature and high pressure, which consists of coupled alternate layers of hydroxide and hydronium.
Michiel Sprik - One of the best experts on this subject based on the ideXlab platform.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
Journal of Chemical Physics, 2019Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counterions from the solution to form electric double layers. In a previous work [T. Sayer et al., J. Chem. Phys 147, 104702 (2017)], we reported on a classical force field based molecular dynamics study of a prototype model system, namely, a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems [half the surface charge density for NaCl(111)]. It was demonstrated that the application of a finite macroscopic field E canceling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field D. The benefits of using D instead of E as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics, as shown in this work.
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finite electric displacement simulations of polar Ionic Solid electrolyte interfaces application to nacl 111 aqueous nacl solution
arXiv: Chemical Physics, 2018Co-Authors: Thomas Sayer, Michiel Sprik, Chao ZhangAbstract:Tasker type III polar terminations of Ionic crystals carry a net surface charge as well as a dipole moment and are fundamentally unstable. In contact with electrolytes, such polar surfaces can be stabilized by adsorption of counter ions from solution to form electric double layers (EDLs). In a previous work (J. Chem. Phys 147, 104702 (2017)) we reported on a classical force field based molecular dynamics study of a prototype model system namely a NaCl(111) slab interfaced with an aqueous NaCl solution on both sides. A serious hurdle in the simulation is that the finite width of the slab admits an electric field in the Solid perturbing the theoretical charge balance at the interface of semi-infinite systems (half the surface charge density for NaCl(111)). It was demonstrated that the application of a finite macroscopic field $E$ cancelling the internal electric field can recover the correct charge compensation at the interface. In the present work, we expand this method by applying a conjugate electric displacement field $D$. The benefits of using $D$ instead of $E$ as the control variable are two fold: it does not only speed up the convergence of the polarization in the simulation but also leads to a succinct expression for the biasing displacement field involving only structural parameters which are known in advance. This makes it feasible to study the charge compensating phenomenon of this prototype system with density functional theory based molecular dynamics (DFTMD), as shown in this work.
Yanchao Wang - One of the best experts on this subject based on the ideXlab platform.
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high pressure partially Ionic phase of water ice
Nature Communications, 2011Co-Authors: Yanchao Wang, Hanyu Liu, Li Zhu, Hui WangAbstract:Dissociation of ice into an Ionic Solid is rare due to the high energy cost of proton transfer. In this study, structure search simulation is used to predict the formation of a partially Ionic phase in ice at low temperature and high pressure, which consists of coupled alternate layers of hydroxide and hydronium.
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high pressure partially Ionic phase of water ice
Nature Communications, 2011Co-Authors: Yanchao Wang, Hanyu Liu, Li Zhu, Hui WangAbstract:Water ice dissociates into a superIonic Solid at high temperature (>2,000 K) and pressure, where oxygen forms the lattice, but hydrogen diffuses completely. At low temperature, however, the dissociation into an Ionic ice of hydronium (H3O)+ hydroxide (OH)− is not expected because of the extremely high energy cost (∼1.5 eV) of proton transfer between H2O molecules. Here we show the pressure-induced formation of a partially Ionic phase (monoclinic P21 structure) consisting of coupled alternate layers of (OH)δ− and (H3O)δ+ (δ=0.62) in water ice predicted by particle-swarm optimization structural search at zero temperature and pressures of >14 Mbar. The occurrence of this Ionic phase follows the break-up of the typical O–H covalently bonded tetrahedrons in the hydrogen symmetric atomic phases and is originated from the volume reduction favourable for a denser structure packing. Dissociation of ice into an Ionic Solid is rare due to the high energy cost of proton transfer. In this study, structure search simulation is used to predict the formation of a partially Ionic phase in ice at low temperature and high pressure, which consists of coupled alternate layers of hydroxide and hydronium.
