scholarly journals Modeling giant planets and brown dwarfs

2010 ◽  
Vol 6 (S276) ◽  
pp. 473-474
Author(s):  
Andreas Becker ◽  
Nadine Nettelmann ◽  
Ulrike Kramm ◽  
Winfried Lorenzen ◽  
Martin French ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
High Pressure ◽  
Equation Of State ◽  
Density Functional ◽  
Brown Dwarfs ◽  
Md Simulations ◽  
Giant Planets ◽  
Functional Theory ◽  
State Data

AbstractWe present new results in modeling the interiors of Giant Planets (GP) and Brown Dwarfs (BD). In general models of the interior rely on equation of state data for planetary materials which have considerable uncertainties in the high-pressure domain. Our calculations are based on ab initio equation of state (EOS) data for hydrogen, helium, hydrogen-helium mixtures and water as the representative of all heavier elements or ices using finite-temperature density functional theory molecular dynamics (FT-DFT-MD) simulations. We compare results for the BD Gliese 229B calculated with Saumon-Chabrier-Van Horn EOS (SCVH95) and our EOS data.

scholarly journals Polydopamine and eumelanin molecular structures investigated with ab initio calculations

2017 ◽  
Vol 8 (2) ◽  
pp. 1631-1641 ◽  
Author(s):  
Chun-Teh Chen ◽  
Francisco J. Martin-Martinez ◽  
Gang Seob Jung ◽  
Markus J. Buehler
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Dft Calculations ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Density Functional ◽  
Md Simulations ◽  
Molecular Structures ◽  
Brute Force ◽  
Functional Theory

A set of computational methods that contains a brute-force algorithmic generation of chemical isomers, molecular dynamics (MD) simulations, and density functional theory (DFT) calculations is reported and applied to investigate nearly 3000 probable molecular structures of polydopamine (PDA) and eumelanin.

Simulating Surfactant-Iron Oxide Interfaces: From Density Functional Theory to Molecular Dynamics

2019 ◽  
Author(s):  
Carlos Ayestaran Latorre ◽  
James Ewen ◽  
Chiara Gattinoni ◽  
Daniele Dini
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Iron Oxide ◽  
Dft Calculations ◽  
Density Functional ◽  
Md Simulations ◽  
Oxide Surfaces ◽  
Interaction Energies ◽  
Functional Theory ◽  
Oxide Interfaces

<div>Understanding the behaviour of surfactant molecules on iron oxide surfaces is important for many industrial applications. Molecular dynamics (MD) simulations of such systems have been limited by the absence of a force-feild (FF) which accurately describes the molecule-surface interactions. In this study, interaction energies from density functional theory (DFT) + U calculations with a van der Waals functional are used to parameterize a classical FF for MD simulations of amide surfactants on iron oxide surfaces. The Original FF, which was derived using mixing rules and surface Lennard-Jones (LJ) parameters developed for nonpolar molecules, were shown to signi cantly underestimate the adsorption energy and overestimate the equilibrium adsorption distance compared to DFT. Conversely, the Optimized FF showed excellent agreement with the interaction energies obtained from DFT calculations for a wide range of surface coverages and molecular conformations near to and adsorbed on a-Fe2O3(0001). This was facilitated through the use of a Morse potential for strong chemisorption interactions, modi fied LJ parameters for weaker physisorption interactions, and adjusted partial charges for the electrostatic interactions. The Original FF and Optimized FF were compared in classical nonequilibrium molecular dynamics (NEMD) simulations of amide molecules con fined between iron oxide surfaces. When the Optimized FF was employed, the amide molecules were pulled closer to the surface and the orientation of the headgroups was more similar to that observed in the DFT calculations compared to the Original FF. The Optimized FF proposed here facilitates classical MD simulations of amide-iron oxide interfaces in which the interactions are representative of accurate DFT calculations.</div>

Stabilization of DPPC lipid bilayers in the presence of co-solutes: molecular mechanisms and interaction patterns

2021 ◽  
Author(s):  
Fabian Keller ◽  
Andreas Heuer ◽  
Hans-Joachim Galla ◽  
Jens Smiatek
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Lipid Bilayers ◽  
Density Functional ◽  
Molecular Mechanisms ◽  
Md Simulations ◽  
Water Molecules ◽  
Interaction Patterns ◽  
Conceptual Density Functional Theory ◽  
Functional Theory

The interactions between DPPC lipid bilayers in different phases with ectoine, amino ectoine and water molecules are studied by means of atomistic molecular dynamics (MD) simulations and conceptual density functional theory (DFT) calculations.

C2N: an excellent two-dimensional monolayer membrane for He separation

2015 ◽  
Vol 3 (42) ◽  
pp. 21351-21356 ◽  
Author(s):  
Lei Zhu ◽  
Qingzhong Xue ◽  
Xiaofang Li ◽  
Tiantian Wu ◽  
Yakang Jin ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
First Principles ◽  
Density Functional ◽  
Md Simulations ◽  
Separation Performance ◽  
Two Dimensional ◽  
Functional Theory

Using the first-principles density functional theory (DFT) and molecular dynamics (MD) simulations, we investigate the He separation performance of a porous C2N monolayer synthesized recently.

Molecular motions in a fluxional (η6-indenyl)tricarbonylchromium hemichelate: a density functional theory molecular dynamics study

2018 ◽  
Vol 47 (27) ◽  
pp. 8906-8920 ◽  
Author(s):  
Nicolas Sieffert
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Density Functional ◽  
Md Simulations ◽  
Atomic Level ◽  
Molecular Motions ◽  
Comprehensive Understanding ◽  
Intramolecular Dynamics ◽  
Functional Theory

DFT-MD simulations provided atomic-level insights into the intramolecular dynamics of a highly fluxional Pd(ii) hemichelate and a comprehensive understanding of the thermodynamics and the kinetics associated with each motion.

scholarly journals Simulating Surfactant-Iron Oxide Interfaces: From Density Functional Theory to Molecular Dynamics

2019 ◽  
Author(s):  
Carlos Ayestaran Latorre ◽  
James Ewen ◽  
Chiara Gattinoni ◽  
Daniele Dini
Keyword(s):  
Molecular Dynamics ◽  
Density Functional Theory ◽  
Iron Oxide ◽  
Dft Calculations ◽  
Density Functional ◽  
Md Simulations ◽  
Oxide Surfaces ◽  
Interaction Energies ◽  
Functional Theory ◽  
Oxide Interfaces

<div>Understanding the behaviour of surfactant molecules on iron oxide surfaces is important for many industrial applications. Molecular dynamics (MD) simulations of such systems have been limited by the absence of a force-feild (FF) which accurately describes the molecule-surface interactions. In this study, interaction energies from density functional theory (DFT) + U calculations with a van der Waals functional are used to parameterize a classical FF for MD simulations of amide surfactants on iron oxide surfaces. The Original FF, which was derived using mixing rules and surface Lennard-Jones (LJ) parameters developed for nonpolar molecules, were shown to signi cantly underestimate the adsorption energy and overestimate the equilibrium adsorption distance compared to DFT. Conversely, the Optimized FF showed excellent agreement with the interaction energies obtained from DFT calculations for a wide range of surface coverages and molecular conformations near to and adsorbed on a-Fe2O3(0001). This was facilitated through the use of a Morse potential for strong chemisorption interactions, modi fied LJ parameters for weaker physisorption interactions, and adjusted partial charges for the electrostatic interactions. The Original FF and Optimized FF were compared in classical nonequilibrium molecular dynamics (NEMD) simulations of amide molecules con fined between iron oxide surfaces. When the Optimized FF was employed, the amide molecules were pulled closer to the surface and the orientation of the headgroups was more similar to that observed in the DFT calculations compared to the Original FF. The Optimized FF proposed here facilitates classical MD simulations of amide-iron oxide interfaces in which the interactions are representative of accurate DFT calculations.</div>

Sign in / Sign up

Export Citation Format

Share Document