The ångström (Swedish: [ˈɔŋstrøm]) or angstrom is a unit of length equal to 10−10m (1 ten-billionth of a meter) or 0.1 nanometers(nm).
Its symbol is Å, a letter in the Swedish alphabet.
The natural sciences and technology often use ångström to express sizes of atoms, molecules, microscopic biological structures, and lengths of chemical bonds, arrangement of atoms in crystals, wavelengths of electromagnetic radiation(light), and also dimensions of integrated circuit parts.
Atoms of phosphorus, sulfur, and chlorine are about an angstrom in covalent radius, while a hydrogen atom is about half an angstrom.
The ångström is named after the Swedish physicist Anders Jonas Ångström (1814–1874).
The symbol is always written with a ring or circle diacritic , as the letter in the Swedish alphabet.
The unit's name is often written in English without the diacritics, but the official definitions contain diacritics.
Videos & Exhibits: