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  2. Laporte rule - Wikipedia

    en.wikipedia.org/wiki/Laporte_rule

    The Laporte rule is a rule that explains the intensities of absorption spectra for chemical species. It is a selection rule that rigorously applies to atoms, and to molecules that are centrosymmetric, i.e. with an inversion centre. It states that electronic transitions that conserve parity are forbidden. Thus transitions between two states that ...

  3. Selection rule - Wikipedia

    en.wikipedia.org/wiki/Selection_rule

    The Laporte rule is a selection rule formally stated as follows: In a centrosymmetric environment, transitions between like atomic orbitals such as s-s, p-p, d-d, or f-f, transitions are forbidden. The Laporte rule (law) applies to electric dipole transitions, so the operator has u symmetry (meaning ungerade, odd).

  4. Electron excitation - Wikipedia

    en.wikipedia.org/wiki/Electron_excitation

    A third rule is the Laporte Rule, which necessitates that the two energy states between which an electron transitions must have different symmetry. A fourth rule is that when an electron undergoes a transition, the spin state of the molecule/atom that contains the electron must be conserved. [8]

  5. Charge-transfer band - Wikipedia

    en.wikipedia.org/wiki/Charge-transfer_band

    The weaker d–d transitions are potentially spin-allowed but always Laporte-forbidden. [2] Charge-transfer bands of transition metal complexes result from shift of charge density between molecular orbitals (MO) that are predominantly metal in character and those that are predominantly ligand in character. If the transfer occurs from the MO ...

  6. Chiefs officiating: A look at the key controversies ... - AOL

    www.aol.com/sports/chiefs-officiating-look-key...

    The Chiefs got away with one late in a win at the Atlanta Falcons. Safety Bryan Cook clearly committed a pass inference penalty on Pitts in the end zone, and the officials missed it.

  7. Upconverting nanoparticles - Wikipedia

    en.wikipedia.org/wiki/Upconverting_nanoparticles

    Finally, this host lattice ought to have low symmetry, allowing for a slight relaxation of the Laporte selection rules. The normally forbidden transitions lead to an increase in the f-f intermixing and thus enhancement of the upconversion efficiency. Other considerations about the host lattice include choice of cation and anions.

  8. What's the difference between NFL's exclusive, non-exclusive ...

    www.aol.com/whats-difference-between-nfls...

    The one-year value of the non-exclusive tag is worth either the average of the top five salaries at a player's position over the last five years or 120% of his previous salary. The tag is worth ...

  9. Al Roker Just Shared the High-Protein, Low-Carb ... - AOL

    www.aol.com/al-roker-just-shared-high-223540111.html

    Unfortunately, no one knows exactly what’s in the rub—except McConaughey and his wife—because it’s a tightly held family secret. Since it’s a rub for grilling meat, it most likely ...