CHEM01200604009 Sreejith Kaniyankandy - Homi Bhabha ...

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In the above expression reactant is in ground vibrational state “0” and product is in higher
vibrational state of index n .
n
2 s
0 | n
exp( s)
n!
and
s
h
i
(1.35)
If we include all vibrations then we get,
2
4
2
ket
HRP
( FC)
(1.36)
h
FC is the Franck-Condon Factor which is sum of all contributions solvation and vibration.
1. 7. Interfacial Electron Transfer from Molecular Adsorbate to
Semiconductor
ET in a semiconductor-dye system is a heterogeneous process. In this case electron
transfer involves coupling between multitudes of semiconductor band levels with frontier
orbitals of the dye molecules with a change in phase at the interfaces. In some of the
cases investigate in the thesis we investigate electron transfer in such systems.
The theoretical framework for such processes was independently developed by Marcus
[1.45], Gerischer [1.46], and Levich and Dogonadze [1.47]. In unconfined systems or so
called bulk semiconductors delocalized band states and trap states contribute towards ET
process. While all the states need to be considered in building an ET theory, description
of trap states are more complicated due to it energetic heterogeneity etc. The ET process
described in the paper mostly involves ET from molecular adsorbate to semiconductor
CB and BET.