title: A hierarchical structure for apatite crystals.
abstract: Based on the experimental results taken from the references, a reasonable hierarchical structure of apatite (both fluorapatite and hydroxyapatite) crystals has been proposed for the first time. The structure consists of four levels of the hierarchy: the smallest level is made of single unit-cells and/or Posner's clusters with the linear dimensions slightly below 1 nm, the second level comprises X-ray coherent scattering blocks of 50-80 nm in size, the third level is represented by dislocation blocks of 0.3-2.0 microm in size and, finally, there are macroblocks of 35-50 microm in size.
authors.affiliation: Kudrinskaja sq. 1 - 155, 123242 Moscow D-242, Russia. sedorozhkin@yandex.ru
authors.forename: Sergey V
authors.initials: SV
authors.lastname: Dorozhkin
mesh_terms: D001031:Apatites / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry; D003460:Crystallization / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D001031:Apatites; D001672:Biocompatible Materials