16 Efficient Singlet Fission in Acene-Based Molecular Assemblies
283
Table 16.3 Summarized
parameters such as singlet
lifetimes (τ S ), SF rate
constants (k SF ) and triplet
quantum yields (Φ T )
Compound
τ S , ps (k S1 , s −1 )
k SF , s −1c
Φ T , % d
TP-Ref
1.5 × 10 4a (6.7 ×
10 7 )
–
1.5 e
TP-C7-S-MPC
24 b (4.1 × 10 10 ) 2.7 × 10 10 157 ± 17 f
TP-C7-L-MPC
54 b (1.9 × 10 10 ) 5.0 × 10 9 77 ± 15 f
TP-C11-S-MPC 21 b (4.8 × 10 10 ) 4.1 × 10 10 172 ± 26 f
TP-C11-L-MPC 110 b (9.1 × 10 9 ) 2.4 × 10 9 34 ± 4 f
Mix-C7-MPC
71 a (1.4 × 10 10 )
–
–
Mix-C11-MPC 150 b (6.7 × 10 9 ) –
–
Reprinted with permission from Ref. [21]. Copyright 2016 WileyVCH
a Estimated by picosecond fluorescence lifetimes
b Estimated by decay component lifetimes
c k SF = 1/τ (TP-Cn-X-MPC) – 1/τ (Mix-Cn-MPC)
d The detail calculation processes are described in the original paper
e Estimated by nanosecond transient absorption spectra
f Estimated by femtosecond transient absorption spectra
Finally, photophysical behaviors of tetracene-alkanethiol-modified MPCs are
discussed (Fig. 16.6). As discussed above, the examples of high-yield and longlived triplet excited states of tetracene derivatives via singlet fission are extremely
limited because of the relative acceleration of the reverse TTA considering the abovementioned energy matching. Then, we also demonstrated a novel technique utilizing
the mixed self-assembled monolayers with two different chain lengths. Especially,
Fig. 16.6 A schematic
illustration of
tetracene-modified gold
nanoclusters. Reprinted with
permission from Ref. [24].
Copyright 2019 American
Chemical Society
283
Table 16.3 Summarized
parameters such as singlet
lifetimes (τ S ), SF rate
constants (k SF ) and triplet
quantum yields (Φ T )
Compound
τ S , ps (k S1 , s −1 )
k SF , s −1c
Φ T , % d
TP-Ref
1.5 × 10 4a (6.7 ×
10 7 )
–
1.5 e
TP-C7-S-MPC
24 b (4.1 × 10 10 ) 2.7 × 10 10 157 ± 17 f
TP-C7-L-MPC
54 b (1.9 × 10 10 ) 5.0 × 10 9 77 ± 15 f
TP-C11-S-MPC 21 b (4.8 × 10 10 ) 4.1 × 10 10 172 ± 26 f
TP-C11-L-MPC 110 b (9.1 × 10 9 ) 2.4 × 10 9 34 ± 4 f
Mix-C7-MPC
71 a (1.4 × 10 10 )
–
–
Mix-C11-MPC 150 b (6.7 × 10 9 ) –
–
Reprinted with permission from Ref. [21]. Copyright 2016 WileyVCH
a Estimated by picosecond fluorescence lifetimes
b Estimated by decay component lifetimes
c k SF = 1/τ (TP-Cn-X-MPC) – 1/τ (Mix-Cn-MPC)
d The detail calculation processes are described in the original paper
e Estimated by nanosecond transient absorption spectra
f Estimated by femtosecond transient absorption spectra
Finally, photophysical behaviors of tetracene-alkanethiol-modified MPCs are
discussed (Fig. 16.6). As discussed above, the examples of high-yield and longlived triplet excited states of tetracene derivatives via singlet fission are extremely
limited because of the relative acceleration of the reverse TTA considering the abovementioned energy matching. Then, we also demonstrated a novel technique utilizing
the mixed self-assembled monolayers with two different chain lengths. Especially,
Fig. 16.6 A schematic
illustration of
tetracene-modified gold
nanoclusters. Reprinted with
permission from Ref. [24].
Copyright 2019 American
Chemical Society