Compared to other diffraction techniques, the advantage of x-ray diffraction is that it enables:

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11ecba2d_1320_6f66_a3bf_bb5b1f73ac91_MD0008_00 Not all forms of electromagnetic radiation undergo diffraction when incident upon one or more slits. For example, x-rays are a form of electromagnetic radiation that cannot undergo classic slit diffraction because the wavelengths of x-rays range from 1 × 10⁻¹¹ m to 10 × 10⁻¹¹ m, which is always exceeded by the lengths of industrially fabricated slits. However, the wavelength of some x-rays is comparable to the typical distance between atoms within the molecular structure of most materials. Consequently, exposing a sample of a purified and crystallized material to x-ray radiation may produce a diffraction pattern unique to that particular substance. When two x-ray waveforms approach and depart a crystalline lattice at an identical incident angle, the waveforms may constructively interfere such that a bright spot is observed on a piece of film distant to the material. The occurrence of constructive interference is a function of the incident angle (θ), the distance between atoms (d), and an integer multiple (n = ±1, ±2, ±3…) of the x-ray wavelength (λ): 11ecba2d_1320_9677_a3bf_8f97570f6d0e_MD0008_00 Because the crystalline lattice of many materials exceeds the complexity of simple crystals, the pattern of bright spots produced on the photographic film is indicative of a molecule's three-dimensional structure and its packing orientation within the crystal lattice. (Choice B) Calculating the kinetic energy of electrons ejected due to the absorption of energy from incident light is applicable in modeling the photoelectric effect, but x-ray diffraction does not cause the ejection of electrons. (Choice C) Using a reference substance with known three-dimensional structure might allow the wavelength of x-ray waveforms to be determined experimentally using x-ray crystallography. However, other diffractive techniques can more easily determine the wavelength of incident light. (Choice D) Electromagnetic radiation can be passed through a linear polarization filter to reveal the original polarization. However, this phenomenon does not involve diffraction and is not specific to x-rays. Educational objective: X-rays diffract within molecules because the space between atoms is comparable to the wavelength of x-rays. X-ray diffraction through a sample of a purified and crystallized material can be used to determine its three-dimensional molecular structure and packing.

Compared to Other Diffraction Techniques, the Advantage of X-Ray Diffraction