1. Question 1 - Simulated Annealing
- I ran the code used in class. I started off with a square lattice and ran a simulation with 100000 steps at 1000K:
I received a nearly perfect triangular lattice, but there is a noticeable defect. Therefore, I decided to try again at 1200K:
A perfect triangular lattice can be observed. Next, I checked whether fewer steps are sufficient and ran it again with 50000 steps at 1200K:
Again, a noticeable defect can be observed (marked in red). After 80000 steps at 1200K:
and it can be seen that 80000 steps are sufficient to get a triangular lattice.
- Next, I wanted to see what happens if you raise the temperature again after cooling for a while, so I ran the simulation for 50000 more steps at 200K and no meaningful change was observed, followed by 80000 more steps at 1500K and still no apparent change so I tried 80000 more steps at 2000K and the triangular lattice still remains, but you can notice that it is not perfect and the lines are not completely straight:
I have to admit that I expected the lattice to be broken but the simulation was very stable.
- I also checked what happens when starting from a random lattice and started with the same conditions that gave me a triangular lattice before - 80000 steps at 1200K, but unfortunately the lattice received was not perfect:
but after 100000 steps:
a perfect triangular lattice was received. My conclusion is that starting from a random lattice requires more steps or higher temperature than starting from a square lattice.
2. Question 2 - Review of a project from previous years
I chose to review David Mazvovsky's project - tubeXYZ
This project features a tool for creating .xyz files ,which are used for visualization in Aviz, of a nanotube with specified chirality.
The atoms of the tube can be carbon, boron or silicon.
The program was written in Fortran 95, implementing the polyhedral model (Lee,Cox and Hill
) for calsulating the coordinated of the requested NT.
The project website is very clear and easy to navigate. The instructions are also very clear and detailed and easy to operate.
I created two Carbon nanotubes with chirality vectors (5,0) and (3,3) and here is the visualization in Aviz of the .xyz file created by the tool:
I think this is a very good project, especially because it is very user friendly. This is a great visualization tool.
3. Question 3 - Seminars Summary
- Blackbody Radiation Emitted by an Arbitrary Shape Body Using the Source Model Technique
- Structure and parameter estimation of high-dimensional Graphical Models
4. Question 4 - My personal homepage
5. Question 5 - Drawing a lattice using AViz
I chose to draw a graphite lattice using AViz with this