- Simulate VSEPR uses placeholders only: A is the central atom and X are the attached atoms. Add or remove bonds and lone pairs; the class, electron geometry, shape and bond angles follow the VSEPR rules. Counts with no VSEPR shape are flagged, and the last valid drawing stays on screen.
- Real molecules pick a measured molecule. Its bond angles are measured where the literature has a value (labelled measured) and follow the VSEPR rule elsewhere (labelled VSEPR rule). The net dipole adds bond dipoles only, from electronegativity differences.
- Lone pairs take fixed slots around the centre atom. They set the electron geometry and the bond angles, but they never pull on the bonds, so they add nothing to the net dipole.
- In a bond angle, < means the angle is squeezed below its ideal value by lone pairs. A plain value such as 109.5° is an undistorted, ideal angle.
- Ions such as NO2- or H3O+ are read as neutral atom sets. Their charge is not modelled.
- Bonds can be single, double or triple (click a bond, or use Bond types). Orders are drawn and listed only: they never change the class, the angles or the verdict.
Also try Chemulate Polarity
Inspired by PhET Molecule Shapes (PhET Interactive Simulations, University of Colorado Boulder, phet.colorado.edu). Independent implementation; not affiliated with or endorsed by PhET.
Chemulate VSEPR