TOTAL ALIGNMENT OF CALCITE AT ACIDIC POLYDIACETYLENE FILMS - COOPERATIVITY AT THE ORGANIC-INORGANIC INTERFACE

Biological matrices can direct the absolute alignment of inorganic cry stals such as calcite. Cooperative effects at an organic-inorganic int erface resulted in similar co-alignment of calcite at polymeric Langmu ir-Schaefer films of 10,12-pentacosadiynoic acid (p-PDA). The films nu cleated calcite at the (012) face, and the crystals were co-aligned wi th respect to the polymer's conjugated backbone. At the same time, the p-PDA alkyl side chains reorganized to optimize the stereochemical fi t to the calcite structure, as visualized by changes in the optical sp ectrum of the polymer. These results indicate the kinds of interaction s that may occur in biological systems where large arrays of crystals are co-aligned.