THE EXISTENCE OF STRUCTURE PROGRESSIONS AND WETTING TRANSITIONS IN INTERMEDIATELY DISORDERED MONOLAYER ALKYL CHAIN ASSEMBLIES

Partial monolayers of uniform length alkyl chains [CH3(CH2)(n)-;n=10-2 1] bonded at constant coverage onto a disordered lattice of silanol gr oups on amorphous SiO2, exhibit a distinct change in surface wetting b ehavior for 14 less than or equal to n less than or equal to 17 which correlates closely with a significant shift in the average conformatio nal ordering of the chains. These data provide definitive evidence for the existence of a family of surface-constrained, intermediately orde red phases of discrete length, flexible chains and imply that broad cl asses of these families exist.