Designing carbon nanotubes (CNTs) manually can be a time-consuming and error-prone process for molecular modelers. SAMSON offers a solution that makes this task more visual, interactive, and reproducible by leveraging pattern creation tools. In this post, we’ll walk through how to build a carbon nanotube one ring at a time using SAMSON’s pattern editors—without relying on specialized nanostructure generators.
Why build manually?
Though SAMSON includes a dedicated Carbon Nanotube Editor, designing a CNT manually gives you full control over geometry, spacing, and atomic connectivity. This is helpful if you’re exploring customized arrangements, specific bonding conditions, or wish to animate the construction process for educational or presentation purposes.
Step-by-step guide: From ring to tube
We start by constructing a single carbon ring. In the following workflow, we replicate and arrange this ring using SAMSON’s Circular and Linear Pattern Editors. You can find these tools in the Editors Toolbar or by pressing the associated shortcut keys.
- Create the initial ring: Use SAMSON’s molecule building tools to draw a hexagonal carbon ring. Remove hydrogen atoms and align the ring flat within the XY plane using the move and rotate tools.
- Form the cylindrical cross-section: Activate the Circular Pattern Editor (press
W) to replicate the ring. - Set the number of instances to 12.
- Adjust the radius until the ends of the carbon atoms align to form bonds.
- Click Accept to finalize the ring loop. Overlapping atoms at the edges will merge automatically if you have this enabled in preferences.
- Stack the rings vertically: Activate the Linear Pattern Editor (press
L) and select the circular ring you just built. - Translate the duplicated rings along the Z-axis (e.g., 2 Å between copies).
- If needed, incrementally rotate each instance to match bond alignment between rings.
- Click Accept to build the full tube.
- Finalize the structure: Once you’ve built the nanotube, use the Minimization tool to relax geometries and automatically adjust hydrogen atoms if needed.
Advantages of this approach
- High flexibility: Design arbitrary CNT lengths and diameters.
- Parameter control: Adjust number of atoms, ring angle, and spacing accurately.
- Educational value: Visualize and explain nanotube construction interactively.
This method is especially useful for research in nanotechnology and educational demonstrations in materials science. For best results, toggle on settings like automatic atom merging under Preferences > Edit > Create pattern.
For a video demonstration of this process, check out the SAMSON 2025 webinar extract.
To learn more, visit the full documentation page: https://documentation.samson-connect.net/users/latest/creating-patterns/
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON at https://www.samson-connect.net