Free Molecular Orbital Diagram Generator for Chemistry

Choose O₂ or N₂ in the generator and select Generate MO Diagram. The tool fills supported ground-state valence orbitals from lower to higher energy, places electrons singly in degenerate π orbitals before pairing, and shows the completed energy diagram with electron counts, bond order and magnetism.

In this qualitative teaching model, s–p mixing puts π2p below σ2p for the supported B₂, C₂ and N₂ species. For O₂, F₂ and Ne₂, σ2p sits below π2p. The generator labels the order used for each result, so you can compare the two diagrams directly.

Subtract the number of antibonding electrons from bonding electrons, then divide by two: bond order = (bonding − antibonding) ÷ 2. For each supported species, the result panel lists both electron counts and the calculated bond order beside the orbital diagram. Compare two species to see how electron filling changes that value.

CO and NO are heteronuclear molecules and require a different orbital-energy treatment from this tool’s supported homonuclear teaching set. The generator accepts listed neutral diatomics from H₂ through Ne₂ plus H₂⁺, N₂⁺, O₂⁺, O₂⁻ and O₂²⁻. Unsupported formulas produce a clear message instead of a guessed diagram.

This generator shows qualitative ground-state occupancy for its supported species. It does not let you set spin multiplicity, move electrons into an excited configuration, or calculate quantum-chemical orbital energies. Use the displayed energy levels as a teaching schematic and verify any excited-state assignment with a method designed for that problem.

Download the generated diagram as SVG for a scalable figure or PNG for slides and worksheets at no charge. The same formats are available for a side-by-side comparison sheet containing two supported species. Generation and export run in your browser without an account, credits or a watermark; review the qualitative-model note before scientific reuse.

Generate the first supported molecule or ion, then choose another species in the comparison panel. Both diagrams appear side by side with their σ/π ordering, bond order, unpaired electrons and magnetism. Download comparison SVG or PNG to place the two diagrams on one sheet for a chemistry worksheet, report or lesson.

Open the O₂, N₂, F₂ or B₂ example cards to load that species into the generator. O₂ shows two unpaired π* electrons and paramagnetism; N₂ has bond order 3; F₂ has bond order 1; B₂ has unpaired π bonding electrons. Each diagram can be downloaded as SVG or PNG.