The phases of insoluble monolayers: Comparison between the surface pressure-molecular area (Π-A) diagram and shear modulus measurements

Simultaneous measurements of the surface pressure‐molecular area (Π‐A) diagrams and the shear modulus of a series of long chain aliphatic alcohols C18OH, C20OH, C21OH, and C22OH spread on water indicate that the conventional phase assignments based on the compressibility are not reliable.