Element | radius (Å) |
---|---|
Hydrogen | 1.2 (1.09)[1] |
Carbon | 1.7 |
Nitrogen | 1.55 |
Oxygen | 1.52 |
Fluorine | 1.47 |
Phosphorus | 1.8 |
Sulfur | 1.8 |
Chlorine | 1.75 |
Copper | 1.4 |
van der Waals radii taken from Bondi's compilation (1964).[2] Values from other sources may differ significantly (see text) |
The van der Waals surface of a molecule is an abstract representation or model of that molecule, illustrating where, in very rough terms, a surface might reside for the molecule based on the hard cutoffs of van der Waals radii for individual atoms, and it represents a surface through which the molecule might be conceived as interacting with other molecules.[citation needed] Also referred to as a van der Waals envelope, the van der Waals surface is named for Johannes Diderik van der Waals, a Dutch theoretical physicist and thermodynamicist who developed theory to provide a liquid-gas equation of state that accounted for the non-zero volume of atoms and molecules, and on their exhibiting an attractive force when they interacted (theoretical constructions that also bear his name). van der Waals surfaces are therefore a tool used in the abstract representations of molecules, whether accessed, as they were originally, via hand calculation, or via physical wood/plastic models, or now digitally, via computational chemistry software. Practically speaking, CPK models, developed by and named for Robert Corey, Linus Pauling, and Walter Koltun,[3] were the first widely used physical molecular models based on van der Waals radii, and allowed broad pedagogical and research use of a model showing the van der Waals surfaces of molecules.