How to make heterojunction in Materials Studio

Modeling steps: 

1: Make all crystals into rectangular cubes (diamonds should also be converted into rectangular shapes). Get two lattice parameters a1, b1, c1; a2, b2, c2 (Note C is generally not needed) 

2: Find the least common multiple of the lattice parameter. Note: This common multiple is relative. For example, the common multiple of 4 and 5 is 20, and the common multiple of 3.8 and 5.1 is also 20. 

3: Obtain the least common multiples a, b, and c of the three lattice parameters respectively (because c is generally not needed, so ignore) 

4: expand the package of crystal 1 (a/a1, b/b1); expand the package of crystal 2 (A/a2, b/b2) 

5: Build a sufficiently large crystal (without atoms) (Note that the a-axis of the newly created crystal lattice should be slightly larger than any a-axis (for example, larger than 0.5a) after you expand the package, Same for b, c at random 

6: copy crystal 1 to enter, copy crystal 2 to enter, and separate the interface between crystals 1 and 2 by a suitable distance (3-5 angstroms). All atoms are in the lattice (this is why it is said above The reason why the new crystal is larger than the previous crystal) 

7: If you are modeling in MS, remember to adjust the display mode to origin. Rebuild the lattice and slightly reduce the lattice parameters (new a and b axes) (due to the new creation above) first larger lattice), for example, the value 0.1 angstroms; expanded into supercell 2 * 2 after reconstruction, the bond between the primary cells and observation of the original even if the normal cell. repeating the steps of the reconstruction process 7 , until the key The connection is slightly reasonable . Note that after the preliminary model is established, please strictly review your own model!!! (The model established by referring to my steps above does not have the problem of unsuccessful optimization, so be sure to check your own model!!! ) 

8: Fix all parameters except a and b axis for structural optimization. 

9: After optimizing without false frequency, the heterogeneous node model is successfully established.


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SiH/TiO2 and GeH/TiO2 Heterojunctions: Promising TiO2-based Photocatalysts under Visible Light, for example, such a heterojunction, the author said it was made by the following method: 

Hello: I used the model created by Material Studio. The smallest unit of TiO2 and SiH lattice matching: 

(1) Cut the surface of TiO2 (101) and add a vacuum layer. 

(2) Prepare the supercell of SiH, construct its rectangular matching unit, and delete extra atoms. 

(3) Change the lattice parameters of TiO2 (101) to be consistent with rectangular SiH, add rectangular SiH to the surface of TiO2, and adjust the distance. 

(4) For the constructed heterogeneous crystal lattice setting, I used the average value of TiO2 and SiH. 

(5) Optimize the lattice constant, then optimize the structure, and calculate the electronic structure.


Source: http://bbs.keinsci.com/thread-3295-1-2.html

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