u
AB
i
¼
R k 2
k 1
u
AB
i ðkÞr AB ðkÞdk
R k 2
k 1
r AB ðkÞdk
¼
R k 2
k 1
r
AB
i ðkÞdk
R k 2
k 1
r AB ðkÞdk
:
ð4:1:27Þ
Virtually, this ratio is the ratio of the oscillator strength of the optical transition
corresponding to i-th photodecay channel to the sum of the oscillator strengths
of all transitions taking place within the band [2, 3, 9]. Its value is characteristic
of the optical transition probability for AB photodecay into i-th channel, this
value is very useful in theoretical evaluations.
6. The absolute integral quantum yield for the formation of the product of AB
photodecay, B i , is found to be as follows:
U
AB
i
¼
R k 2
k 1
U
AB
B i
ðkÞr AB ðkÞdk
R k 2
k 1
r AB ðkÞdk
¼
R k 2
k 1
r
AB
i ðkÞdk
R k 2
k 1
r AB ðkÞdk
;
ð4:1:28Þ
where r AB (k) is the AB absorption cross-section.
7. The convolution quantum yield of i-th primary photoprocess within the band
k j Ä k k is defined as follows:
u
AB;c
i
k j À k k
À
Á ¼
R k j
k k
u
AB
i ðkÞU hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
R k j
k k
U hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
ð4:1:29Þ
where U hm (k), photon/(s Á nm) is the spectral photon flux passing into the
photochemical cell, l is the cell length.
8. The convolution quantum yield for the formation of the B photoproduct is
calculated to be as follows:
U
AB;c
i
k j À k k
À
Á ¼
R k j
k k
U
AB
B i
ðkÞU hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
R k j
k k
U hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
ð4:1:30Þ
In a typical case, values of the u
AB;c
i
k j À k k
À
Á
, U
AB;c
i
k j À k k
À
Á
are determined by
the mutual position of the curves U hm (k), r AB (k), u
AB
i , and the [AB], l quantities. Hence, the convolution quantum yields are dependent on experimental
conditions, i.e., they all are incommensurable quantities. Nevertheless, you may
often encounter articles, where authors deal with photolysis processes with very
weak intensities in a wide spectral range, wherein the quantum yields of the
photoprocesses have not constant values.
4.1 Primary and Secondary Processes of Gas-Phase Photolysis …
85
AB
i
¼
R k 2
k 1
u
AB
i ðkÞr AB ðkÞdk
R k 2
k 1
r AB ðkÞdk
¼
R k 2
k 1
r
AB
i ðkÞdk
R k 2
k 1
r AB ðkÞdk
:
ð4:1:27Þ
Virtually, this ratio is the ratio of the oscillator strength of the optical transition
corresponding to i-th photodecay channel to the sum of the oscillator strengths
of all transitions taking place within the band [2, 3, 9]. Its value is characteristic
of the optical transition probability for AB photodecay into i-th channel, this
value is very useful in theoretical evaluations.
6. The absolute integral quantum yield for the formation of the product of AB
photodecay, B i , is found to be as follows:
U
AB
i
¼
R k 2
k 1
U
AB
B i
ðkÞr AB ðkÞdk
R k 2
k 1
r AB ðkÞdk
¼
R k 2
k 1
r
AB
i ðkÞdk
R k 2
k 1
r AB ðkÞdk
;
ð4:1:28Þ
where r AB (k) is the AB absorption cross-section.
7. The convolution quantum yield of i-th primary photoprocess within the band
k j Ä k k is defined as follows:
u
AB;c
i
k j À k k
À
Á ¼
R k j
k k
u
AB
i ðkÞU hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
R k j
k k
U hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
ð4:1:29Þ
where U hm (k), photon/(s Á nm) is the spectral photon flux passing into the
photochemical cell, l is the cell length.
8. The convolution quantum yield for the formation of the B photoproduct is
calculated to be as follows:
U
AB;c
i
k j À k k
À
Á ¼
R k j
k k
U
AB
B i
ðkÞU hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
R k j
k k
U hm ðkÞ 1 À exp r AB ðkÞ AB
½ l
f
g
f
g dk
ð4:1:30Þ
In a typical case, values of the u
AB;c
i
k j À k k
À
Á
, U
AB;c
i
k j À k k
À
Á
are determined by
the mutual position of the curves U hm (k), r AB (k), u
AB
i , and the [AB], l quantities. Hence, the convolution quantum yields are dependent on experimental
conditions, i.e., they all are incommensurable quantities. Nevertheless, you may
often encounter articles, where authors deal with photolysis processes with very
weak intensities in a wide spectral range, wherein the quantum yields of the
photoprocesses have not constant values.
4.1 Primary and Secondary Processes of Gas-Phase Photolysis …
85