Lewis Structure

Lewis Structure for macOS makes drawing clear, accurate Lewis dot structures fast and frustration-free for chemistry students and educators. It combines an interactive periodic table, smart valence guides, and flexible export and sharing so your diagrams are ready for class, homework, or publication.

What the app does

—Create Lewis structures by placing elements on a blank canvas, then adding unpaired or paired electrons, single, double, dashed double, and triple bonds, brackets, and charges.

—Start from an element’s typical valence configuration and adjust electrons, brackets, and charges to represent ions and different bonding situations.

—Export finished structures as transparent PNG images so they drop cleanly into documents, slides, worksheets, and online materials.

Key features

—Interactive periodic table to quickly select any element and place it on the canvas with its usual valence electrons for the neutral atom.

—Optional on-canvas guides around each element showing valid electron positions, helping students visualize lone pairs and bonding pairs more clearly.

—Click-based bonding workflow: choose a bond type, click one atom then another, and click bonds again to cycle through available bond types as you refine the structure.

Editing and notation

—Add, remove, and reposition electrons to explore alternative structures, resonance forms, or formal charge arrangements while staying consistent with Lewis rules.

—Apply positive or negative charges, then click to cycle through allowed magnitudes, making it easy to represent polyatomic ions and charged species.

—Turn guides on or off at any time; guides are purely visual aids and never appear in exported PNG images, keeping outputs clean and publication-ready.

Saving, sharing, and compatibility

—Save your work in the dedicated Lewis Structure document format (.lewis) so you can revisit, revise, and reuse structures across courses and semesters.

—Share .lewis files with colleagues or students and import files from others to streamline collaboration and feedback on structure assignments.

—Open and use these same .lewis files inside the Lewis structure module of the Chemistry Dude app, providing a smooth workflow across your teaching tools.