Structural adaptability in an organic template for CaCO3 mineralization

Biomimetic strategies to control mineral nucleation include the development of self-assembled monolayers with appropriate structural properties. We present a bis-urea based surfactant with variable structural adaptability, which induces habit modification in calcite crystals under optimal conditions. In situ surface-sensitive synchrotron X-ray scattering measurements are reported, which yield surprising conclusions for the film structure. In particular, it is found that nucleation of modified calcite is correlated with the release of two-dimensional ordering in the surfactant layer. The model system is discussed in the context of the history of Langmuir films as models for biomineralization.