Oriented crystallization of calcium carbonate under self-organized monolayers of amide-containing phospholipids

In the presence of calcium ions amide-containing phospholipid 1 self-assemb les to form well-defined two-dimensional domains at the air-water interface . These domains act as templates for the crystallization of calcium carbona te that efficiently nucleate the growth of [10.0] oriented calcite irrespec tive of the surface concentration of the lipid. Responsible for this prefer ence for nucleation at the (10.0) face is the formation of an intramolecula r hydrogen bond between the phosphate group and the phenoxy moiety which fo rces the phosphate group to adopt a bidentate orientation toward the aqueou s phase. It was shown that when this hydrogen bond was absent, that is, whe n the phosphate group is monomethylated, lateral pressure was required in o rder to enforce a similar conformation and accomplish the nucleation of [10 .0] oriented calcite.