Final answer:
X-ray diffraction (XRD) is the tool used to detect the pattern of atoms in a crystal. It involves analyzing the diffraction pattern produced by the scattering of X-rays from the crystal which reveals information about its crystal structure.
Step-by-step explanation:
The tool used to detect the pattern of atoms in a crystal is X-ray diffraction (XRD). This technique involves the scattering of X-rays from a crystal to produce a diffraction pattern, which can then be analyzed to determine the crystal structure. X-ray diffraction is a fundamental tool in crystallography and was famously utilized by Rosalind Franklin in the research that contributed to the discovery of the double helix structure of DNA.
In addition to confirming the size and shape of atoms, XRD provides detailed information about atomic arrangements within materials. This is particularly useful in fields like material science, where the precise arrangement of atoms can affect the properties of materials, such as the superconductivity in high-temperature superconductors.