Influence of radial TEM distortion on the accuracy of lattice parameter determinations of apatites: a comparison of four electron microscopes.
Lattice fringe distances of synthetic hydroxyapatite were measured quantitatively in four different TEM microscopes as a function of the position with respect to the optical axis. Using the accurately known "a" value of this apatite from X-ray diffraction, the maximum radial distortion in the image planes can be determined in various positions. For the Philips EM 400, EM 300 (1) and EM 300 (2) and JEOL 200 CX the maximum radial distortion was found to be 1.0%, 0.8%, 1.5% and 0.5%, respectively. In accurate lattice parameter determinations of mineral and mineral phases in biological tissues by means of TEM; this radial distortion is an important parameter to take into account.
D003461:Crystallography; D006882:Hydroxyapatites; D007089:Image Enhancement; D008854:Microscopy, Electron / Q000295:instrumentation*
D006882:Hydroxyapatites