BEH.462/3. 962J Molecular Principles of Biomaterials Spring 2003 How are free energy barriers modified by organic templates?(Mann 1993)Complementarity in 1. Surface lattice geometries 2. Spatial charge distributions 3. Polarity of hydration layers 4. Defect sites 5. Bonding chemist Coordination environment of metal ion in crystal mimicked by binding to organic surface groups Fig. 6.28 Free energy curves for nucleation in the absence (1) and presence o Matching lattice geometries Organic templating layer 5 New crystal Nucleation of the calcite 110 face under car- boxylate monolayers( B)Nucleation of the cal- cite(001)face under sulfate monolayers Mann et al. 1993 itching charge distributio Case of calcium cabonate: different crystal structures and crystal orientations nucleated on different charge surfaces Lecture 12-Inorganic biomaterials 2of13BEH.462/3.962J Molecular Principles of Biomaterials Spring 2003 • How are free energy barriers modified by organic templates? (Mann 1993) Complementarity in: 1. Surface lattice geometries 2. Spatial charge distributions 3. Polarity of hydration layers 4. Defect sites 5. Bonding chemistry ƒ Coordination environment of metal ion in crystal mimicked by binding to organic surface groups o Matching lattice geometries: Organic templating layer New crystal (Mann et al. 1993) o Matching charge distributions: ƒ Case of calcium cabonate: different crystal structures and crystal orientations nucleated on different charge surfaces Lecture 12 – Inorganic Biomaterials 2 of 13