Bohrsäännön

Bohrsäännön, also known as Bohr's rule, is a fundamental principle in atomic physics that describes the behavior of electrons in atoms. It was formulated by the Danish physicist Niels Bohr in 1913 as part of his model of the atom. The rule states that electrons can only occupy specific, discrete energy levels or orbits around the nucleus of an atom. These allowed energy levels are often referred to as stationary states.

Electrons cannot exist at energy levels between these allowed orbits. When an electron absorbs energy, it jumps to a higher energy level. Conversely, when an electron emits energy, it falls to a lower energy level. The energy emitted or absorbed is in the form of a photon, a particle of light. The energy of this photon is precisely equal to the difference in energy between the two levels involved.

This concept of quantized energy levels is a cornerstone of quantum mechanics. Bohr's model, while later superseded by more sophisticated quantum mechanical models, successfully explained the spectral lines of hydrogen and provided a crucial step in understanding atomic structure. The idea that electrons occupy specific orbits with defined energies explained why atoms emit and absorb light at characteristic wavelengths, forming the basis of spectroscopy. Bohrsäännön, therefore, is essential for understanding atomic emission and absorption spectra, chemical bonding, and the properties of matter.