01
Draw.
Build a structure, change bonds, and try out rings. Start from scratch, open an example, or import a SMILES string.
Explore the editorDraw molecules in 2D, explore their geometry in 3D, and understand what each bond changes. An open space for teaching and learning organic chemistry.
Free to use. No account needed to draw. Yours to explore.
See Rotamer in actionTHE ROTAMER WORKBENCH2D 3D
Actual editor screenshot · aspirin · interface in Portuguese
GROUNDED IN CHEMISTRY
RDKit validation and descriptors
MMFF94 geometry and dynamics
Open source from sketch to source code
INSIDE THE WORKBENCH
Watch chemistry
in action.
Demonstrations recorded in Rotamer, with captions to follow every step.
From sketch to space
No audio · English captions · app interface in PortugueseFollow ethanol being built, bond by bond, and watch its geometry appear alongside it.
The video could not be loaded. Open the MP4 file or follow the transcript below.
Read transcript
From sketch to space
- One click creates the first carbon. Dragging connects the second carbon.
- The oxygen tool is selected and a bond adds oxygen to the chain, forming ethanol.
- RDKit validates the structure; the 3D geometry is calculated using MMFF94.
- The drawing is arranged using the editor command. The 3D scene is rotated while molecular dynamics remain visible.
Explore a molecule
- Aspirin is loaded from the examples menu, and the structure takes shape in space.
- The analysis panel is opened, showing the functional groups and descriptors calculated by RDKit.
- The 3D scene is rotated to view the molecule from another angle. Geometry and dynamics are calculated using MMFF94.
Watch a molecule vibrate
- The analysis panel is opened. Water is loaded using the SMILES string O, and RDKit validates the structure.
- The 3D scene is rotated. The panel shows the molecule’s three normal modes.
- The first mode is selected to observe bending; another mode is then shown for comparison. The amplitude is increased and the motion slowed down for visualization. Frequencies are calculated using MMFF94, not measured in a spectrum.
- The mode is deselected, and the scene returns to molecular dynamics.
CHOOSE WHAT TO EXPLORE
You set the pace. Choose a video and press play to begin.
01 / FROM IDEA TO MOLECULE
Chemistry you
can explore.
The structure leaves the board. Its shape takes form in space. And every discovery is backed by a calculation.
02
Observe.
Watch the calculated geometry take shape, rotate the 3D model, and explore molecular dynamics and normal modes of vibration.
Explore the 3D view03
Understand.
Read the formula, mass, functional groups, and descriptors. See what is calculated and what is a hypothesis from the optional tutor.
Understand the analysisACCURACY BELONGS IN EDUCATION
The core calculates.
AI explains.
Valence, aromaticity, and descriptors come from RDKit. Geometry and dynamics come from the MMFF94 force field. The tutor reads these results and helps interpret them.
Each analysis identifies its source in the interface. Without an AI key, the editor and written hints still work.
See how it worksEvery number has a source.
RDKit for chemistry. MMFF94 for geometry. The mission engine for objectives and scoring.
Explanations open up possibilities.
The optional tutor suggests ways to interpret the result. It does not calculate descriptors or decide whether a mission is complete.
Optional AI · explanations labeled on screen02 / A SPACE TO LEARN
From your curiosity
to your next lesson.
A workbench to explore on your own. A tool to develop questions with your class.
For learners
Practice in the Structure, Geometry, and Property tracks. In the Optimization track, explore freely, without missions or scores.
For teachers
Create classes, organize assignments, and set a mission by drawing the answer. See where your class needs help.
03 / OPEN DOCUMENTATION
Your next step
starts here.
From your first sketch to your own instance. Complete guides, with search and navigation by topic.
FOR USERS01
Start with a sketch
Your first molecule, tools, shortcuts, analysis, and 3D exploration.
Read the user guideFOR HOSTS02Bring it to your school
Docker, configuration, the first administrator, updates, and data backups.
Install RotamerFOR CONTRIBUTORS03Join the project
Set up your environment, explore the architecture, and learn how to contribute.
Contribution guide04 / HOST IT YOURSELF
At your school.
On your server.
The app and Postgres run with Docker. You manage the instance and keep the data in your own volume.
Full installation guideCovers configuration, the first administrator, HTTPS, updates, and backups.
TERMINAL · BASH / ZSH
git clone https://github.com/GabrielMello1407/Rotamer.git
cd Rotamer
cp .env.example .envBEFORE YOU BEGIN
A few answers.
No mystery.
Do I need to pay or create an account?
Rotamer is free and MIT-licensed. The editor opens without registration. An account lets you save progress, join classes, and use the instance’s authoring features.
Do I need an AI key?
No. A Gemini key only enables the tutor. Drawing, calculations, geometry, missions, and written hints work without it.
Does it work on mobile?
Yes. The workbench adapts to smaller screens, and chemistry runs in a browser worker. The editor also respects the reduced-motion preference.
Which features use external services?
Name search and known-compound lookups use PubChem. The tutor uses Gemini when configured. Umami telemetry is off by default. See the services and the data sent.
What can I expect from the results?
Descriptors are calculated by RDKit; geometry and frequencies come from the force field. The frequencies are not experimental spectra. The project does not predict reactions, claim biological activity, or calculate IUPAC names. Understand the project’s limits.
BUILT TO BE SHARED
Chemistry belongs to everyone.
So does the code.
Use it in class. Report a problem. Improve a guide.
Every contribution helps the next person learn.