Spectroscopy comes in many types, depending on the kind of energy a molecule absorbs or emits. Here’s a overview of the main types:
1. UV-Visible Spectroscopy
- What it studies: Absorption of ultraviolet or visible light by molecules.
- What it tells us: Electronic transitions (electrons jumping to higher energy levels).
- Uses: Measuring concentrations, studying chemical reactions, identifying compounds.
2. Infrared (IR) Spectroscopy
- What it studies: Absorption of infrared light.
- What it tells us: Vibrations of bonds in molecules (stretching and bending).
- Uses: Identifying functional groups and molecular structures.
3. Nuclear Magnetic Resonance (NMR) Spectroscopy
- What it studies: How atomic nuclei respond to a magnetic field.
- What it tells us: Molecular structure and arrangement of atoms.
- Uses: Determining chemical structures of organic molecules.
4. Mass Spectroscopy (MS)
- What it studies: Mass of molecules or fragments.
- What it tells us: Molecular weight and molecular structure.
- Uses: Identifying unknown compounds and detecting trace elements.
5. Fluorescence Spectroscopy
- What it studies: Light emitted after a molecule absorbs light.
- What it tells us: Electronic structure, presence of fluorescent molecules.
- Uses: Biological studies, detecting small amounts of substances.
6. Rotational (Microwave) Spectroscopy
- What it studies: Rotations of molecules.
- What it tells us: Molecular shape, bond lengths.
- Uses: Studying small molecules in gases.
7. Raman Spectroscopy
- What it studies: Scattering of light by molecules.
- What it tells us: Vibrations and molecular fingerprints.
- Uses: Material analysis, chemistry, biology.
8. X-ray Spectroscopy
- What it studies: Absorption or emission of X-rays.
- What it tells us: Atomic structure, electron arrangement.
- Uses: Material analysis, crystallography.
- Summary:
- Different spectroscopy types probe different energy changes in molecules—like rotations, vibrations, electronic jumps, or nuclear properties—so together, they give a complete picture of the molecule.