energy level: Quick Facts

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Facts

Also Known As	eigenstate • stationary state • energy level

Photos

A diagram showing the energy levels of a hydrogen atom, with horizontal lines representing quantum levels N=1 through N=6 and infinity. Vertical red lines indicate electron transitions that produce ultraviolet, visible, and infrared light, labeled as series I, II, and III.

energy levels of a luminescent centre

Figure 12: The energy levels of three nuclei with A = 6, relative to the ground state of 6Li after subtraction of the calculated electrostatic energy. The isospin T = 1 levels exist in all three nuclei.

energy states in molecular systems

Figure 5: Energy levels of the neon atom. The orbitals occupied by the six outer electrons are indicated on the levels. The transition responsible for the red light from common lasers (wavelength of 6330 Å) is shown by the arrow.

Figure 15: Energy-level spectrum of the deformed nucleus erbium-164.

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Topics

excitation electronic configuration metastable state Franck-Hertz experiment transition optical pumping shielding molecular energy level quantized level ground state quantum field theory Schrödinger’s cat quantum S-matrix wave mechanics

Key People

James Franck

James Franck

German physicist

Gustav Hertz

Gustav Hertz

German physicist

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

Physics and Natural Law