Obviously, cantilever C4 is acted by two forces: one is the van der Waals force
at the CNT/Au contact interface, and the other is the elastic resilience force resulting from elastic deformation.
The normal and shear stress intensity of the interface that is provided by van der Waals force
can be achieved through the above analysis.
Atoms on different layers of MWNTs are not connected by covalent bonds and the only interaction between them is through van der Waals forces
. Van der Waals forces
are rather weak compared to covalent bonds.
It appears that van der Waals force
has not been addressed directly in previous work, except in the theoretical modeling by Jagota et al.
The total van der Waals force
([F.sup.vdw]) between the tip and substrate can be obtained by adding the forces from Equations (A17) and (A19):
D is 0.34 nm, which is the vertical distance of the attractive van der Waals force
. A is the Hamaker constant between nanotubes :
reported that CNT yarn load capacity can be improved by postspun twisting which is affected by two factors: bringing the CNTs into closer contact with one another and therefore enhancing the van der Waals forces
and higher radial compressive stress .
When the fraction of the surface of each platelet overlapping with another platelet is p, the effective van der Waals force
in the connector direction is:
The repulsive force measured by AFMs is partially offset by a very weak attractive force - the van der Waals force
- that acts between the sample and the probe as they converge to atomic-level distances.
According to the studies, Van der Waals Force
plays an important role in the creation of the bond.
Fullerenes interact through the van der Waals force
, which gives cohesive energies of approximately 1.7 eV per molecule.
Therefore, this research tries to present appropriate mechanical models to apply van der Waals force
between two single-walled carbon nanotubes, and to evaluate the dynamic interaction between them.