Spicing Up Research with Code 1: Carbon Nanotube Structure Generator Dev Diary (1)
Hey there! I’ve created a program that generates NxM CNT (Carbon Nanotube) structures in VASP format. Simply save the text file with a .VASP extension, and you can visualize your carbon nanotube using VESTA.
Think of a CNT as a sheet of graphene (carbon atoms arranged in hexagons) rolled into a cylinder - kind of like that cylindrical honeycomb structure above. I made sure to include vacuum space around the tube for VASP calculations.
Why I Built It
I tried several existing tools but ran into these frustrations:
- Manual calculations were a real headache → So I automated them
- Why install software when you just need a structure file? → Made it web-based
- The manuals were so complicated - like reading research papers! → Simplified the inputs
- Too many terminal commands and setup steps → Created a simple web interface
Cool Features
No Installation, Works Everywhere
Since it’s a web-based JS program, you don’t need to install anything. Works on any operating system!
Super Easy to Use
Just two main inputs! Choose how many carbon hexagons make up your tube (N) and click - that’s it! Want to tweak the C-C bond length? Check that box and change 1.42 to whatever you need. You can even swap carbon for B or N to make BN tubes (though I wonder if anyone will actually use that feature 😄).
How to Use It
Visit: https://suecreamm.github.io/cnt_generator/
Pick either Armchair or Zigzag structure, set how many hexagons you want around the circumference (N), and click. You’ll get a VASP-formatted atomic structure file.
For N values between 5-8, I’ve already created the files - grab them here. For other N values, create a text file in Notepad (Windows) or terminal (Mac, Linux), paste the output, and save with .vasp extension. Drop it into VESTA to see your 3D nanotube!
Development Story
I use a Mac, and it’s frustrating when some programs don’t work on it or break when switching operating systems. That’s why I learned JavaScript to make this web-based tool. Sure, there might be better programs out there, but I felt that installing Python and using terminal commands created unnecessary barriers. If you just need a structure file, why bother with all that setup?
It took about a week to develop.
References & Resources
- Atomic structures: Based on standard definitions
- Calculations: Manually worked out for cylindrical coordinates
- Frontend design: https://html5up.net/solid-state
- Frontend implementation: Mostly improvised as I went along 😅
