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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. Donald Trump taps Sylvester Stallone, Mel Gibson and Jon ...

    www.aol.com/donald-trump-taps-sylvester-stallone...

    The Trump transition team did not immediately respond to a request for comment. All three men have been vocal supporters of the Republican president-elect. In 2019, Voight hailed Trump as "the ...

  7. Transition metal - Wikipedia

    en.wikipedia.org/wiki/Transition_metal

    In centrosymmetric complexes, such as octahedral complexes, d–d transitions are forbidden by the Laporte rule and only occur because of vibronic coupling in which a molecular vibration occurs together with a d–d transition. Tetrahedral complexes have somewhat more intense colour because mixing d and p orbitals is possible when there is no ...

  8. Countries staying committed to climate plans after US Paris ...

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    BRASILIA/WASHINGTON (Reuters) -Countries are staying committed to their national climate plans and looking to lead the clean energy transition, as the United States plans to exit the Paris climate ...

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

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

    Week 3: Missed pass interference on Kyle Pitts. 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 ...