Questions tagged [adsorption]
For questions about modeling the adsorption, the process of molecules attaching to a solid surface.
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Large energy differences across successive geometry optimization steps in SIESTA
I am trying to calculate adsorption energies of acetophenone on a 6x6x3 nickel surface with about 12 Angstrom of vacuum above it using SIESTA 5.
I have arranged the molecule so that the ring plane is ...
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Adsorption of Li on GeC (optimization problem)
Actually I am trying to study the adsorption of Li or K on the sheet starting from the hexagon centre the system optimises with Li or (K) adsorbed over one of the Ge atoms and not remain at the centre....
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Can adsorption energy be upto -8 eV for VOC adsorption in MoS2 layer?
I've been using VASP for DFT calculations and came across with an adsorption energy value over $-8\,eV$.
Is this a reasonable value for S-H bond?
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Adsorption of naphthalene on graphene oxide sheets with gmx
How to set up a molecular dynamics (MD) simulation for the adsorption of naphthalene on graphene oxide sheets using GROMACS?
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What is the Miller index of the highest site?
I am trying to use Pymatgen adsorption module for my adsorption site calculations. While going through the documentation, I had a small confusion. It says the following
Determine “surface sites” by ...
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How to calculate Gibbs free energy of adsorption at constant temperature with varying pressures
I want to calculate the Gibbs free energy of adsorption for an oxidized surface. The literature I consulted used the equations attached to this post. I am trying hard to find my way through. Any idea ...
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How to read a poscar file which is a surface and add adsorbates using ASE
I have a POSCAR file containing Co, Cr, Fe, Ni elements. It is a slab of 6 layers. The first 3 layers are mobile whiles the last three layers are fixed. I would like to add adsorbates at the FCC ...
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Can CP2K be used for slab calculations?
I am trying to map out potential energy of a slab surface + cation interaction, since VASP has been giving me very not-so-reliable results I wanted to know if CP2K have the ability to do such ...
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How the adsorption energies calculated at DFT level, is valid at finite temperatures?
The adsorption energies of atoms or molecules on any surface in a standalone DFT are inherently devoid of any temperature influence. so, let's say an atom/molecule has very weak binding, in ...
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Adsorption of Zn2+ on the metallic surface in VASP
I am trying to model the adsorption of charged atom (Zn2+) on the metallic surface using VASP.
Since NELECT assumes total charge (metallic surface + Zn), is it the right flag to use? Or are there any ...
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Is there a way to estimate the energy of desorption of an adsorbed molecule? [closed]
I'm studying the adsorption of several molecules in metal organic frameworks (MOFs) using both experimental and computational methods. Experimetally I can easily obtain the temperature at which a ...
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XANES simulation software/code besides FEFF for Pt L3 edge?
I need to generate the XANES region spectra of the Pt L3 edge of a theoretical Pt6 crystal with adsorbed atoms/molecules, such as $\ce{Pt(H^*), Pt(O^*), Pt(OH^*),Pt(CO^*)}$. It is for generating ...
7
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How to estimate adsorption energy of Li atom on graphene?
I would like to reproduce the data of adsorption energies published in paper.
For example, they say the adsorption energy for Li atom on graphene is -1.19 eV (estimated by GGA-PBE). I used vasp (5.4) ...
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How can I find the area of an overlayer structure?
What sources would you recommend (or if you could instead explain it to me that would be great). I have never studied crystallography but must do a module on it and in some of the questions we were ...
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Converge number of layers of atoms or number of unit cells for adsorption calculations? [closed]
I'm trying to calculate the adsorption energies of various adsorbates on Fe2O3 surfaces (although, with there being many possible surfaces for Fe2O3 it is quite complex, but that's for another time...)...
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Semi-infinite surfaces for adsorption: a valid approach?
I'm currently trying to surface reaction of small molecules on metal oxides in VASP. Several papers I've read have approached surface energy calculations in a variety of ways. I first began looking at ...
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What are the steps to prepare a solid-solid interface for adsorption studies in plane-wave DFT?
Please, how may one simulate a solid-solid interface that one can carry out adsorption studies from. I tried using virtual nanolab in Quantum ATK but didn't get a hand of it.
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Fermi level change in surfaces with adsorbed molecules
In a DFT standard calculation of a solid 3D material (i.e. bulk metal), one of the properties that can be obtained is the Fermi level $E_F$. This feature is related with the required work to add an ...
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