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3D-Printing Electron Density Isosurface Models and High-Resolution Molecular Models Based on van der Waals Radii

3D printing was used to prepare space-filling models of electron density isosurfaces and high-resolution molecular models on the basis of the van der Waals radii of atoms. Both model types provide students with kinesthetic simulations of steric effects in bimolecular substitution and elimination reactions. The models can be printed in small sizes for individual student use or large sizes for classroom demonstrations. These space-filling models can also enable visually impaired students to experience tangible representations of theoretical surfaces.