enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Atomic orbital - Wikipedia

    en.wikipedia.org/wiki/Atomic_orbital

    For example, the orbital 1s (pronounced as the individual numbers and letters: "'one' 'ess'") is the lowest energy level (n = 1) and has an angular quantum number of ℓ = 0, denoted as s. Orbitals with ℓ = 1, 2 and 3 are denoted as p, d and f respectively. The set of orbitals for a given n and ℓ is called a subshell, denoted

  3. Energy level - Wikipedia

    en.wikipedia.org/wiki/Energy_level

    An increase in energy level from E 1 to E 2 resulting from absorption of a photon represented by the red squiggly arrow, and whose energy is h ν. A decrease in energy level from E 2 to E 1 resulting in emission of a photon represented by the red squiggly arrow, and whose energy is h ν.

  4. Caesium standard - Wikipedia

    en.wikipedia.org/wiki/Caesium_standard

    In the caesium atom it so happens that the sub-level lowest in energy is the one with F = 3, while the F = 4 sub-level lies energetically slightly above. When the atom is irradiated with electromagnetic radiation having an energy corresponding to the energetic difference between the two sub-levels the radiation is absorbed and the atom is ...

  5. Electron configuration - Wikipedia

    en.wikipedia.org/wiki/Electron_configuration

    As an example, the ground state configuration of the sodium atom is 1s 2 2s 2 2p 6 3s 1, as deduced from the Aufbau principle (see below). The first excited state is obtained by promoting a 3s electron to the 3p subshell, to obtain the 1s 2 2s 2 2p 6 3p 1 configuration, abbreviated as the 3p level. Atoms can move from one configuration to ...

  6. Hund's rules - Wikipedia

    en.wikipedia.org/wiki/Hund's_rules

    We need to consider only the outer 3p 2 electrons, for which it can be shown (see term symbols) that the possible terms allowed by the Pauli exclusion principle are 1 D , 3 P , and 1 S. Hund's first rule now states that the ground state term is 3 P, which has S = 1. The superscript 3 is the value of the multiplicity = 2S + 1 = 3.

  7. Principal quantum number - Wikipedia

    en.wikipedia.org/wiki/Principal_quantum_number

    In a simplistic one-electron model described below, the total energy of an electron is a negative inverse quadratic function of the principal quantum number n, leading to degenerate energy levels for each n > 1. [1] In more complex systems—those having forces other than the nucleus–electron Coulomb force—these levels split.

  8. Molecular orbital diagram - Wikipedia

    en.wikipedia.org/wiki/Molecular_orbital_diagram

    Molecular orbital diagrams are diagrams of molecular orbital (MO) energy levels, shown as short horizontal lines in the center, flanked by constituent atomic orbital (AO) energy levels for comparison, with the energy levels increasing from the bottom to the top. Lines, often dashed diagonal lines, connect MO levels with their constituent AO levels.

  9. Degenerate energy levels - Wikipedia

    en.wikipedia.org/wiki/Degenerate_energy_levels

    The energy levels in the hydrogen atom depend only on the principal quantum number n. For a given n , all the states corresponding to ℓ = 0 , … , n − 1 {\displaystyle \ell =0,\ldots ,n-1} have the same energy and are degenerate.