| Abstract: | Binary and pseudobinary compounds AB like NaCl and CaCO3, with the center of charge at carbon position, are characterized by self‐coordination numbers of nearest, second and third neighbors T 1 T 2 T 3 of A and B positions. The maximum Madelung factor of compounds with identical T i values of A and B atoms is obtained for a maximum of B positions at the border of the A–A Dirichlet domain. The A and B positions form a packing with different T i values, if all B positions are on the border of the Dirichlet domain. This packing like the primitive cubic packing of Na and Cl atoms with T i values 6 12 8 or the rhombohedrally distorted packing 6 8 6 of CaCO3 as morphological lattice complexes can be related to cubic NaCl crystals or the cleaved rhombohedron of calcite. A different habit of crystals is expected for sphere, rod or layered packings. Many well‐defined nanoparticles can be obtained from microemulsions at variation of temperature, water content or water partial pressure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) |
