Spectroscopy

The core idea of spectroscopy is that different materials interact with light (or any electromagnetic radiation) in unique ways. When radiation passes through a substance or is emitted by it, specific wavelengths are absorbed or emitted, creating a characteristic pattern or “spectrum”. This pattern is like a fingerprint for the atoms, molecules, or ions in the substance. The positions of the spectral lines (dark for absorption, bright for emission) correspond to the energy differences between quantum states of the material. For example, an electron in an atom can jump to a higher energy level by absorbing a photon of a specific energy, or it can fall to a lower level by emitting a photon. The energy of this photon is directly related to its frequency and wavelength. By analyzing the intensity and position of these lines, scientists can deduce the chemical composition, temperature, density, and motion of the object being studied. This principle applies across the entire electromagnetic spectrum, from radio waves to gamma rays, leading to a vast array of spectroscopic techniques tailored for different types of analysis.