Interfaces between 3D Materials: Copper and SiO2 (Cristobalite).

Introduction.

This tutorial demonstrates the process of creating interfaces between 3D materials, specifically copper (Cu) and cristobalite (SiO₂), based on the work presented in the following manuscript, where the electronic properties of Cu-SiO₂ interfaces are studied.

Manuscript

Shan, T.-R., Devine, B. D., Phillpot, S. R., & Sinnott, S. B. "Molecular dynamics study of the adhesion of Cu/SiO2interfaces using a variable-charge interatomic potential." Physical Review B, 83(11). DOI: 10.1103/PhysRevB.83.115327 ¹.

We use the Materials Designer to create interfaces between Cu and Cristobalite with different termination pairs.

The FIG. 1. shows the interfaces with different terminations between Cu and Cristobalite.

1. Load and Preview Materials.

Navigate to Materials Designer and import copper and cristobalite materials from the Standata.

Then use the JupyterLite environment to create the target structures.

2. Create Interface Between Copper and Cristobalite.

2.1 Launch JupyterLite Session.

Select the "Advanced > JupyterLite Transformation" menu item to launch the JupyterLite environment.

2.2 Open and Modify the Notebook.

Select the input materials with the first being the substrate (SiO₂) and the second being the film (Cu).

Open the create_interface_with_min_strain_zsl.ipynb notebook and modify the parameters as follows:

• Miller indices of both materials: (0, 0, 1) -- as mentioned in the publication.
• Thickness of both materials: 3 (in atomic layers, will resolve to 6 layers for Cu and 9 layers for SiO₂, as mentioned in the publication)
• Distance between materials: 2.4 Å (to achieve Cu-O bond of ~2.4 Å, as stated in the publication's results)
• Interface vacuum: 18.0 Å (as mentioned in the publication)

Let's set MAX_AREA to 150 Ų to allow for a larger search area for the superlattice search algorithm.

TERMINATION_PAIR_INDEX will be set to 0 to get interface with Cu/Si termination and 1 to get Cu/O termination. Terminations for the interfaces can be viewed further down in the notebook.

Adjust the "1.1. Set up slab parameters" cell as shown:

# Enable interactive selection of terminations via UI prompt
IS_TERMINATIONS_SELECTION_INTERACTIVE = False

FILM_INDEX = 1  # Index in the list of materials, to access as materials[FILM_INDEX]
FILM_MILLER_INDICES = (0, 0, 1)
FILM_THICKNESS = 3  # in atomic layers
FILM_VACUUM = 0.0  # in angstroms
FILM_XY_SUPERCELL_MATRIX = [[1, 0], [0, 1]]
FILM_USE_ORTHOGONAL_Z = True

SUBSTRATE_INDEX = 0
SUBSTRATE_MILLER_INDICES = (0, 0, 1)
SUBSTRATE_THICKNESS = 3  # in atomic layers
SUBSTRATE_VACUUM = 0.0  # in angstroms
SUBSTRATE_XY_SUPERCELL_MATRIX = [[1, 0], [0, 1]]
SUBSTRATE_USE_ORTHOGONAL_Z = True

# Maximum area for the superlattice search algorithm
MAX_AREA = 150  # in Angstrom^2
# Set the termination pair indices
TERMINATION_PAIR_INDEX = 0
INTERFACE_DISTANCE = 2.4  # in Angstrom
INTERFACE_VACUUM = 18.0  # in Angstrom

2.3. Run the Notebook.

After setting the parameters, run the notebook to create the interface between Cu and SiO₂.

2.4. View Results.

The generation might take some time. After that, the user can pass the material to the Materials Designer for further analysis.

Interface between Copper and Cristobalite with the specified parameters is shown below.

3. Pass the Material to Materials Designer.

The user can pass the material with the interface in the current Materials Designer environment and save it.

Or the user can save or download the material in Material JSON format or POSCAR format.

4. Create Interfaces with other Terminations.

To create interfaces with other terminations, repeat the steps 1 - 4 and change the TERMINATION_PAIR_INDEX parameter to 1 to get the interface with Cu/O termination.

Or use the interactive selection of terminations by setting IS_TERMINATIONS_SELECTION_INTERACTIVE = True, rerunning the notebook, and selecting the desired termination from the list.

Interactive JupyterLite Notebook.

The interactive JupyterLite notebook for creating interfaces between Copper and Cristobalite is embedded below. To run the notebook, click on the "Run All" button.

⛶ Full Screen

References.

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1. T.-R. Shan, B. D. Devine, S. R. Phillpot, and S. B. Sinnott. Molecular dynamics study of the adhesion of cu/sio2interfaces using a variable-charge interatomic potential. Physical Review B, 2011. URL: https://doi.org/10.1103/PhysRevB.83.115327. ↩