Preferred Label : quantum yield;
Detailed label : quantum yield, Φ;
IUPAC definition : div class 'intro' Number of defined events occurring per u photon absorbed /u by
the system. /div The integral quantum yield is \[\mathit{\Phi}(\lambda) \frac{{number
of events}}{{number of photons absorbed}}\] For a photochemical reaction, \[\mathit{\Phi}(\lambda)
\frac{{amount of reactant consumed or product formed}}{{number of photons absorbed}}\]
The differential quantum yield is \[\mathit{\Phi}(\lambda) \frac{{d}x/{d}t}{q_{n,{p}}
{0}[ 1 - 10 {-A(\lambda)} ]}\] where dx/dt is the rate of change of a measurable quantity
(spectral or any other property), and qn,p0 the amount of photons (mol or its equivalent
einstein) u incident /u (prior to absorption) per time interval (photon flux, amount
basis). Aλ is the absorbance at the excitation wavelength.;
Scope note : fcan be used for photophysical processes (such as, e.g., intersystem crossing, fluorescence
and phosphorescence) or photochemical reactions.; strictly, the term quantum yield applies only for monochromatic excitation. thus,
for the differential quantum yield, the absorbed spectral photon flux density (number
basis or amount basis) should be used in the denominator of the equation above when
x is either the number concentration ( c n v ), or the amount concentration
(c), respectively.;
Origin ID : Q04991;
See also
div class 'intro' Number of defined events occurring per u photon absorbed /u by
the system. /div The integral quantum yield is \[\mathit{\Phi}(\lambda) \frac{{number
of events}}{{number of photons absorbed}}\] For a photochemical reaction, \[\mathit{\Phi}(\lambda)
\frac{{amount of reactant consumed or product formed}}{{number of photons absorbed}}\]
The differential quantum yield is \[\mathit{\Phi}(\lambda) \frac{{d}x/{d}t}{q_{n,{p}}
{0}[ 1 - 10 {-A(\lambda)} ]}\] where dx/dt is the rate of change of a measurable quantity
(spectral or any other property), and qn,p0 the amount of photons (mol or its equivalent
einstein) u incident /u (prior to absorption) per time interval (photon flux, amount
basis). Aλ is the absorbance at the excitation wavelength.
