PHOTONS IN CHEMISTRY OUT

PHOTONS IN CHEMISTRY OUT WHY BOTHER?

1.Remote action

Light has: Intensity Color (wavelength) Polarization

E = h ν

Light has: Intensity Color (wavelength) = ENERGY Polarization

1.Remote action 2.Energetics

(wavelength) x (frequency) = speed [m/s] λν = c [10 8 m/s]

E = h ν

~ nm Take 500 nm

Boltzman

T [ o K]n 2 /n x x x ,0006 x ,0003 x ,4001 % 10, % 20,00024 % 50,00056 %

Boltzman T [ o K]n 2 /n x x x ,0006 x ,0003 x ,4001 % 10, % 20,00024 % 50,00056 %

Boltzman T [ o K]n 2 /n x x x ,0006 x ,0003 x ,4001 % 10, % 20,00024 % 50,00056 %

Boltzman T [ o K]n 2 /n x x x ,0006 x ,0003 x ,4001 % 10, % 20,00024 % 50,00056 %

Boltzman T [ o K]n 2 /n x x x ,0006 x ,0003 x ,4001 % 10, % 20,00024 % 50,00056 %

Grotthuss-Draper law: Only the light absorbed in a molecule can produce photochemical Change in the molecule (1871 and 1841) Stark - Einstein: If a species absorbs radiation, then one particle is excited for each quantum of radiation absorbed

Stark - Einstein: If a species absorbs radiation, then one particle is excited for each quantum of radiation absorbed QUANTUM YIELD: Φ = The number of molecules of reactant consumed for each quantum of radiation absorbed Primary Φ ≤ 1 Sum of all primary Φ’s = 1