Accurate prediction of the properties of materials using the CAM‐B3LYP density functional

Chemical doping and other surface modifications have been used to engineer the bulk properties of materials, but their influence on the surface structure and consequently the surface chemistry are often unknown. Previous work has been successful in fluorinating anatase TiO2 with charge balance achieved via the introduction of Ti vacancies rather than the reduction of Ti. Our work here investigates the interface between this fluorinated titanate with cationic vacancies and a monolayer of water via density functional theory based molecular dynamics. We compute the projected density of states for only those atoms at the interface and for those states that fall within 1eV of the Fermi energy for various steps throughout the simulation, and we determine that the variation in this representation of the density of states serves as a reasonable tool to anticipate where surfaces are most likely to be reactive. In particular, we conclude that water dissociation at the surface is the main mechanism that influences the anatase (001) surface whereas the change in the density of states at the surface of the fluorinated structure is influenced primarily through the adsorption of water molecules at the surface.

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A First-Principles Computational Comparison of the Aqueous Anatase TiO2 (001) Interface and the Disordered, Fluorinated TiO2 Interface

10.26434/chemrxiv.7076816 ◽

2018 ◽

Author(s):

Kyle Reeves ◽

Damien Dambournet ◽

Christel Laberty-Robert ◽

Rodolphe Vuilleumier ◽

Mathieu Salanne

Keyword(s):

Density Of States ◽

Density Functional ◽

Water Dissociation ◽

Water Molecules ◽

Chemical Doping ◽

Charge Balance ◽

Functional Theory ◽

Adsorption Of Water ◽

Properties Of Materials ◽

Computational Comparison

Chemical doping and other surface modifications have been used to engineer the bulk properties of materials, but their influence on the surface structure and consequently the surface chemistry are often unknown. Previous work has been successful in fluorinating anatase TiO2 with charge balance achieved via the introduction of Ti vacancies rather than the reduction of Ti. Our work here investigates the interface between this fluorinated titanate with cationic vacancies and a monolayer of water via density functional theory based molecular dynamics. We compute the projected density of states for only those atoms at the interface and for those states that fall within 1eV of the Fermi energy for various steps throughout the simulation, and we determine that the variation in this representation of the density of states serves as a reasonable tool to anticipate where surfaces are most likely to be reactive. In particular, we conclude that water dissociation at the surface is the main mechanism that influences the anatase (001) surface whereas the change in the density of states at the surface of the fluorinated structure is influenced primarily through the adsorption of water molecules at the surface.

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Accurate prediction of hydration free energies and solvation structures using molecular density functional theory with a simple bridge functional

The Journal of Chemical Physics ◽

10.1063/5.0057506 ◽

2021 ◽

Vol 155 (2) ◽

pp. 024117

Author(s):

Daniel Borgis ◽

Sohvi Luukkonen ◽

Luc Belloni ◽

Guillaume Jeanmairet

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Accurate Prediction ◽

Free Energies ◽

Functional Theory ◽

Molecular Density ◽

Bridge Functional

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From Electronic Structure To Thermodynamics

MRS Proceedings ◽

10.1557/proc-104-13 ◽

1987 ◽

Vol 104 ◽

Cited By ~ 1

Author(s):

Giovanni B. Bachelet

Keyword(s):

First Principles ◽

Lattice Dynamics ◽

Density Functional ◽

Preliminary Test ◽

Computational Effort ◽

Consistent Theory ◽

Amorphous Systems ◽

Trajectory Approach ◽

Properties Of Materials

ABSTRACTA simple way to extend the remarkable results of Density Functional calculations to finite-temperature properties of materials is the quasi-harmonic theory of Lattice Dynamics. In this framework a thermodynamically consistent theory needs the complete phonon spectrum for a large periodic system (30–100 atoms/cell) at many different volumes, which poses severe practical limitations. In this paper I present the application to a semiconducting system of a method recently proposed by Bachelet and De Lorenzi to overcome these limitations. Based on low-temperature Molecular-Dynamics trajectories (now possible from first principles for semiconducting systems according to the method of Car and Parrinello), the method is shown to provide accurate dynamical matrices for an 8-atom silicon supercell. Such a successful, preliminary test, together with the fact that for larger and/or lower-symmetry systems the computational effort required by the “trajectory approach” is lower than traditional frozen-phonon or force-constant techniques, suggests its use in the determination of dynamical matrices of larger defect or amorphous systems, and thus in the study of their thermodynamics from first principles.

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Understanding the ML black box with simple descriptors to predict cluster–adsorbate interaction energy

New Journal of Chemistry ◽

10.1039/d0nj00633e ◽

2020 ◽

Vol 44 (20) ◽

pp. 8545-8553

Author(s):

Sheena Agarwal ◽

Shweta Mehta ◽

Kavita Joshi

Keyword(s):

Density Functional Theory ◽

Interaction Energy ◽

Density Functional ◽

Black Box ◽

Functional Theory ◽

Properties Of Materials ◽

Insight Into

Density functional theory (DFT) is currently one of the most accurate and yet practical theories used to gain insight into the properties of materials.

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