van der Waals kraft mellan partiklar

Okej så van der Waals kraften är normalt attraherande mao repulserande/instabiliserande.

Men om man då här pratar om att metaller har högre värde på A (hammaker konstanten) jämfört med exempelvis organiska ämnen - men SAMTIDIGT säger man att metalliska ämnen är mer "sticky", mao mindre repulserande=de sitter lättare ihop/närmar varandra lättare... hur går detta ihop?

Ett högre värde på A <--> V(a) blir mer negativ i ekvationen nedan = MER attraherande = MER repulserande = MINDRE "sticky"

- eller?

"For example the van der Waals force between
equal-sized spherical colloidal particles of radius R
(see also Chapter 2) is expressed in potential
energy–distance form (V–H) as:
V(a) = −AR/12H
where H is the interparticle or interface distance and R
is the radius of the particle. For the equation to hold,
H << R. Table 2.2 (Chapter 2) shows the expression
for the sphere–flat surface and surface–surface (infinite
thickness) interactions.
It has been shown (Israelachvili, 2011) that for diameters
beyond 0.5 nm a molecule must be considered
a small particle and the equations of Table 2.2 should
be used for the van der Waals forces. The effective
Hamaker constant, which depends on the particles
(chemical composition) and the medium, determines
the effective strength of the vdW interactions.
The Hamaker constant for a given material in vacuum
can have values that typically range between
10–19 and 10–21 J, with higher values for metals (e.g.
40 × 10–20 J for silver) than for organics (e.g. 6.6 ×
10–20 J for polystyrene, 5.4 × 10–20 J for toluene and
4.1 × 10–20 J for hexane). This implies that metal particles
like silver, gold and platinumare much “stickier”
than particles made up of organic materials."