A non-SI unit of length equal to 0.1 nanometers or 10^-10 meters, represented by the symbol Å. It is primarily used in crystallography, solid-state physics and chemistry to express the sizes of atoms, lengths of chemical bonds and wavelengths of electromagnetic radiation. While the nanometer is the preferred SI unit, this traditional measure remains heavily entrenched in structural biology and spectroscopy.
Heard on the job
The gap between the crystal lattice planes measures about three angstroms.
Insider tip
Crystallographers still default to this unit because typical atomic bonds fall neatly between one and two units, avoiding the decimal fractions required by nanometers.