Table 1.

Factors governing the monolayer phase behavior.

Van der Waals interaction: •Short range forces: (ΓVDW ∝ r−6) •Directly proportional to the number of carbon atoms in the hydrocarbon chain for the saturated hydrocarbon •Depends on the presence of double bonds or substituents like methyl group in the chain

Electrostatic interaction: •Ion – Ion (Γii ∝ r−1) •Ion – Dipole (Γid ∝ r−2) •Dipole – Dipole (Γdd ∝ r−3)

The subphase composition: •pH of the subphase •Temperature of the subphase •Type/nature of materials