Van der Waals force

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Revision as of 09:08, 13 February 2016 by Apm (Talk | contribs) (Theory)

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This page is not going to discuss the origin and nature of the VdW force but is focusing on practical applications and an intuitive understanding.

Practical usage

Comparison

(TODO: make a table comparing stiffness force and energy to a single covalent C-C bond by showing equivalent area)

Two coplanar atomically flat surfaces attract each other quite a lot.

  • ~1nN per square nm this equates to around ~10,000 bar.
    Original Source: (Nanosystems 9.7.1.)
    indirect source: [1] (beware: the noted binding energy is mistakenly taken from a covalent interface - Nanosystems 9.7.3.)
    double indirect source: [2]
  • ~2.7nN per square Nm 1/20 the tensile strength of diamond
    Source: (Nanosystems 3.5.1.b) (more than titanium and low grade steel)

They can still slide effortlessly along each other (possibly superlubricating) so depending on the use indents may be needed to prevent that. (intuitive feel)

(TODO: find the missing value)

Theory

Please use external sources - there are plenty out there.
Wikipedia: [3]

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