Van der Waals radius
van der Waals radii are established from contact distances between non-bonding atoms in touching molecules or atoms.
Van der Waals radii may be established from neighbour-neighbour interactions in crystals and from gas critical volumes. Values from tables in different sources differ. Those quoted in WebElements are taken from reference 1 while other marginally different compilations are located in references 2-5. Users of the Chemical Database Service (CDS) at Daresbury who make use of the Cambridge Structural Database System will also find these values reproduced in the "Getting Started" user manual.
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