Chapter 1: Glossary


Blackbody radiation

Radiation from an object due to thermal energy

Bohr model

Model for the hydrogen atom as proposed by Niels Bohr

Bohr radius

Radius of the electron orbit in a hydrogen atom corresponding to the lowest energy energy solution of the Bohr model

de Broglie wavelength

Wavelength of a particle l = h/p

Energy level

The energy which an electron can have


Heat divided by absolute temperature

Fermi energy

The average energy per particle when adding particles to a distribution but without changing the entropy or the volume. Chemists refer to this quantity as being the electro-chemical potential


Particles with half-integer spin

Gauss' law

One of Maxwell's equations, stating that the gradient of the electric field equals the charge density, divided by the dielectric constant.


Thermal energy

Hydrogen atom

An atom consisting of a proton and an electron

Particle-wave duality

Quantum mechanical concept, which states that particles can behave as waves and waves can behave as particles

Photoelectric effect

Emission of electrons from a metal when applying light with photon energy larger than the workfunction of the metal


Quantum of electromagnetic radiation

Poisson's equation

Second order differential equation which relates the potential, f, to the charge density, r.

Quantum mechanics

Theory which describes particles by a wavefunction


Unit of atomic energy = 13.6 eV


Atomic states which are associated with one principle quantum number


A single solution to Schrödinger's equation defined by a unique set of quantum numbers

Thermal energy

Energy associated with the temperature of an object

Thermal equilibrium

A system is in thermal equilibrium if every ongoing process is exactly balanced by its inverse.

Wave packet

Wave description of a localized particle


Mechanical energy

Work function

Potential an electron at the Fermi energy needs to gain to escape from a solid