Atomic Interactions: Lennard-Jones Potential
Drag two atoms and see the attractive and repulsive forces and the Lennard-Jones potential graph.
Drag one atom towards the other and watch the Lennard-Jones potential energy graph and the force arrows. Atoms attract when far apart and repel when squeezed.
About the Atomic Interactions: Lennard-Jones Potential
Free atomic interactions: lennard-jones potential. Drag two atoms and see the attractive and repulsive forces and the Lennard-Jones potential graph. Drag, change the sliders and see the result live. No sign-up, works on phone and computer. Built for chemistry, the atomic interactions: lennard-jones potential runs instantly in your browser: change a setting or drag an object and the result updates at once, so you learn by trying things out rather than only reading about them.
Drag two atoms and see the attractive and repulsive forces and the Lennard-Jones potential graph. Use it to explore chemistry ideas at your own pace, then check what you found against the key ideas further down this page.
How to use the Atomic Interactions: Lennard-Jones Potential
- Use the controls to change Atoms, Motion. The simulation reacts instantly.
- Pick an option such as Neon, Argon, Oxygen O₂, Drag freely to switch modes or load an example.
- Press "Reset" to start, reset or change what is happening.
- Where you see a glowing handle, object, weight or atom, drag it with your mouse or finger. Everything responds in real time.
- Watch the readouts and graphs update as you experiment, and compare what you see with the key ideas below.
Things to try
- Find the equilibrium distance for argon.
- Switch to neon and compare the depth.
- Let the atoms move and watch them vibrate.
Key ideas you can learn
- Atoms attract at long range and repel when squeezed.
- The energy minimum is the equilibrium distance.
- A deeper well means stronger attraction.
- Forces come from the slope of the potential.
Where this is used in the real world
This model explains why gases condense, why liquids form and how molecules pack.
Who is this simulation for?
Chemistry students from middle school to university, teachers who need a virtual demonstration, and anyone without access to a lab. It is safe, free and repeatable as many times as you like.
For teachers: project it on the board, let students predict what will happen, then run it together. For students: change one thing at a time and write down what changes.
Frequently asked questions
What is the Lennard-Jones potential?
A simple model of the potential energy between two neutral atoms with attraction and repulsion.
Why do atoms not collapse into each other?
At very short distance the repulsion becomes very strong.
Is the Atomic Interactions: Lennard-Jones Potential free to use?
Yes. It is completely free, with no signup, no download and no ads inside the simulation. It runs in your web browser.
Does the Atomic Interactions: Lennard-Jones Potential work on a phone or tablet?
Yes. It uses touch as well as the mouse, so you can drag objects with your finger. A larger screen makes the controls easier to see.