When working with molecular models, a common early task is to measure distances between atoms or bond lengths. Whether you are building a new molecule, comparing structures, or preparing to simulate interactions, knowing exact measurements is vital. However, navigating measurement tools in a 3D molecular environment can sometimes be tedious or unclear.
If you’ve ever found yourself wondering: “Did I already measure that bond length?” or “Where did that distance label go?”, then you’ll appreciate how SAMSON’s Measure editor simplifies this process greatly.
Effortless Measuring at a Glance
SAMSON includes a dedicated editor for measuring geometric properties like distances, angles, and dihedrals. You can activate it either from the left-hand menu in the viewport (look for the 📏 ruler icon), or by pressing Ctrl + M (or Cmd + M on macOS).
Here’s how it works for atom distances:
- Click on two atoms to instantly see the distance between them displayed in the 3D viewport.
- To save this measurement so it persists with your document and is editable, press
Enter. - Unsaved measurements are temporary and automatically replaced by the next one.
Pro tip: If you want to highlight several distances at once (for comparisons or presentations), press Enter after each measurement to save it as a label. Temporary measurements are limited to one at a time.
More Than Numbers
Once saved, measurements are turned into labels that integrate into the document tree and are fully customizable. You can:
- Change font, size, and color.
- Modify distance line and angle plane colors using the Inspector panel.
- Choose how many decimal places to show for precision.
In cases where you also want to check how atomic distances project onto specific planes, SAMSON displays this information automatically in the Inspector when selecting a labeled distance.
Stay Updated as You Work
Another useful feature: measurements update automatically as atoms move or their properties change. This is particularly practical when tweaking geometries with the Move editors or running interactive minimizations.
This means you can use the Measure editor not just for checking structure, but also for monitoring structural changes during simulation prep—without having to remeasure manually.
Final Thought
Distance measurements may seem basic, but managing them efficiently plays an essential role in keeping your modeling workflow smooth and organized. By offering both ephemeral and persistent visualizations, and making them easily customizable and always up-to-date, SAMSON helps streamline a habitual task many molecular modelers deal with every day.
To learn more about measurements in SAMSON, visit the official documentation page.
SAMSON and all SAMSON Extensions are free for non-commercial use. Get SAMSON at https://www.samson-connect.net.