ADSORPTION ISOTHERMS discontinuous jumps: layering transitions some layering transitions coexistence pressure monolayer condensation bilayer condensation

 =

two-phase region liquid-vapour transition of monolayer two-phase region

at two-phase coexistence

 

Y(s)Y(s) Y (  s ) = Q (  s )

if there exists  such that there is a wetting transition, this is of 2 nd order Y(s)Y(s)

COMPLETE WETTING T=T W COMPLETE WETTING T>T W PARTIAL WETTING T<T W PARTIAL WETTING T<T W

area under curve

contribution from hard interaction contribution from attractive interaction (with correlations = step function)

a  b  a  < s a(T W )  a  b  s <