Designing carbon nanotubes (CNTs) manually may sound like a complex task, but figuring it out offers a useful exercise for researchers working in nanotechnology and molecular design. In real-world scenarios, researchers often need customized nanotube structures to match specific properties or geometric constraints. This blog post introduces a pattern-based approach made possible by SAMSON’s Pattern Editors, enabling you to construct carbon nanotubes interactively and with fine-tuned control over the structure.
If you’ve ever struggled to manually align patterns of rings into a tube-like shape, you’re not alone. Traditional molecular editors make such workflows tedious, involving repetitive transformations. Pattern Editors in SAMSON streamline this task with visual tools and intuitive controls.
Step-by-step: Build Your Own Nanotube
The following workflow walks you through the process of building a CNT manually using SAMSON’s Circular and Linear Pattern Editors:
- Create a Carbon Ring: Start by building a simple carbon ring in SAMSON. Remove any hydrogen atoms to prevent steric conflicts and rotate the ring as needed to align edge atoms.
- Create a Closed Loop with the Circular Pattern Editor (W):
- Activate the Circular Pattern Editor by pressing
W. - Increase the number of copies (e.g., 12) to complete a ring pattern.
- Adjust the radius manually (using the widget or by entering numerical values) so that outer atoms are close enough to form covalent bonds with neighbors.
- Click Accept to finalize the circular assembly.
- Activate the Circular Pattern Editor by pressing
- Align the Ring on the XY Plane: Use Edit > Align to place the circular ring on a reference axis, ensuring consistent stacking direction.
- Stack the Rings with the Linear Pattern Editor (L):
- Select the ring and activate the Linear Pattern Editor (keyboard shortcut
L). - Define translations along the Z-axis—for example, 2 Å between copies—to start creating a tubular shape.
- Use rotation if needed, to alternate connections between layers.
- Accept to generate the tube.
- Select the ring and activate the Linear Pattern Editor (keyboard shortcut
- Minimize the Structure for Realism: Finally, use the Minimization tool to relax the geometry and optionally add hydrogen atoms to satisfy valencies.
This manual construction is not only a practical tutorial—it also gives you full control over radius, orientation, step size, and rotation. You can better tailor the tube for simulations or functionalization studies, beyond what’s available with predefined nanotube generators.
When to Use This Method
This approach is ideal when you need devices or architectures with non-standard geometries or connections—such as junctions, kinks, or functional handles at specific locations. By learning to build your nanotube manually, you gain a foundation to explore more complex nanoscale systems.
Visual Example
Learn more about pattern creation in SAMSON, including curved duplication and structure organization tips.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can download SAMSON here.