röntgendiffraktsiooni

Röntgendiffraktsioon, also known as X-ray diffraction (XRD), is a powerful analytical technique used to determine the atomic and molecular structure of a crystal. When X-rays interact with a crystalline material, they are scattered in specific directions due to the regular arrangement of atoms within the crystal lattice. This scattering pattern, known as a diffraction pattern, is unique to the material's crystal structure.

The principle behind röntgendiffraktsioon is Bragg's Law, which describes the condition for constructive interference of X-rays scattered by parallel planes of atoms in a crystal. Bragg's Law states that nλ = 2d sinθ, where n is an integer representing the order of diffraction, λ is the wavelength of the X-rays, d is the spacing between the atomic planes, and θ is the angle of incidence of the X-rays. By measuring the angles at which diffraction occurs, scientists can determine the d-spacings.

A röntgendiffraktsioon experiment typically involves directing a beam of monochromatic X-rays onto a powdered or single-crystal sample. A detector then records the intensity of the diffracted X-rays as a function of the scattering angle. The resulting diffraction pattern, often presented as a plot of intensity versus 2θ, contains a series of peaks that correspond to specific crystal planes. Analysis of these peaks allows for the identification of the crystalline phase, determination of lattice parameters, and even assessment of crystallite size and strain.

Röntgendiffraktsioon finds widespread application in various scientific disciplines, including materials science, chemistry, physics, geology, and pharmaceuticals. It is used for material identification, phase analysis, quality control, and studying phase transformations.