Diffraktogrammin

Diffraktogrammin is a graphical record produced in diffraction experiments used to study crystalline materials. It plots the scattered intensity versus the diffraction angle (usually 2θ) and is generated in X-ray, neutron, or electron diffraction. The pattern shows peaks arising from constructive interference by sets of crystal planes.

Peak positions relate to interplanar spacings through Bragg's law, enabling identification of crystalline phases by matching the measured 2θ values to reference data. Peak intensities reflect the arrangement of atoms and, together with quantitative methods, allow estimation of phase fractions and crystal symmetry.

The diffraktogrammin is used for phase identification, lattice parameter determination, and quantitative phase analysis (often via Rietveld refinement of the full pattern). Peak widths provide information about crystallite size and microstrain, with the Scherrer equation used for rough estimates.

Common instruments are X-ray diffractometers for powder diffraction, electron diffraction in transmission electron microscopes, and neutron diffractometers. Data processing includes background subtraction, peak fitting, and pattern indexing. Amorphous content manifests as broad humps, while overlapping peaks can complicate interpretation.

Limitations include instrumental broadening, preferred orientation, sample quality, and the need for standards. Overall, the diffraktogrammin is a central tool in materials science, geology, and mineralogy for revealing crystal structures, phase composition, and microstructural characteristics.