Nanometer: A nanometer is a unit of length in the metric system, equal to one-billionth of a meter. Nanometers are used to measure extremely small distances, such as the wavelength of light or the size of atoms and molecules.
Angstrom: An Angstrom is a unit of length equal to one-tenth of a nanometer, or one-hundred-millionth of a centimeter. It is commonly used to measure the size of atoms, molecules, and other microscopic structures.
Infrared Radiation: Infrared radiation is a type of electromagnetic radiation with wavelengths longer than those of visible light, but shorter than those of radio waves. It is commonly used in infrared spectroscopy to study the chemical composition and structure of materials.