How Can DFT Methods Model Twin Energy in Crystals?

[knghrts17]

Hello all,


I am attemtping to model crystal twinning using DFT methods. In particular I wish to look at the twin energy as a function of twin angle in a hcp system. I am running into difficulty however in attempting to create my repeat unit prior to my calculations. I was wondering if anybody had some suggestions on how to do this. For example, say I wished to have a twin angle [tex]\theta[/tex] = 30^o. How could I go about defining this given a defect free (perfect) bulk crystal.


Thanks in advance!

 

[eljose79]

Hello,

I am also a scientist working with DFT methods and I have some suggestions for you.

Firstly, when creating your repeat unit, you can consider using software such as VESTA or Materials Studio to build your crystal structure with the desired twin angle. These software allow you to manipulate the crystal structure and create twin boundaries at specific angles.

Alternatively, you can also use the lattice parameters of the perfect bulk crystal and manually create a supercell with the desired twin angle using a scripting language like Python or MATLAB. This may require some trial and error to find the correct lattice parameters for the desired twin angle.

Additionally, you can try using the twin energy equation derived from DFT calculations to calculate the energy of the twin boundary at different angles. This will give you an idea of the energy landscape and help you determine the most stable twin angle for your system.

I hope these suggestions will be helpful for your research. Good luck!