In this quantum approach,
by adding bridge/π-spacer fragments
between the donor and acceptor parts of a newly constructed DF-PCIC
(A–D–A type) molecule, it is the aim to improve the
photovoltaic characteristics of organic solar cells (OSCs). After
π-spacer insertion into the reference molecule (DF-R), six new molecules (DF-M1 to DF-M6) were
designed. The optoelectronic attributes of newly inspected molecules
were theoretically calculated using MPW1PW91/6-31G(d,p) level of theory.
All newly proposed molecules possessed a lower band gap (E
g), a higher value of absorption, lower reorganization
energy, greater dipole moment, and lower energies of excitations than
the DF-R molecule. The frontier molecular orbital study
proclaimed that the DF-M1 molecule has the lowest band
gap of 1.62 eV in comparison to the 2.41 eV value of DF-R. Absorption properties represented that DF-M1 and DF-M2 molecules show the highest absorption values of up to
1006 and 1004 nm, respectively, in the near-infrared region. Regarding
the reorganization energy, DF-M2 has the lowest value
of λe (0.0683896 eV) and the lowest value of λh (0.1566471 eV). DF-M2 and DF-M5 manifested greater dipole moments with the values of 5.514665 and
7.143434 D, respectively. The open circuit voltage (V
OC) of all the acceptors was calculated with J61, a donor complex. DF-M4 and DF-M6 molecules
showed higher values of V
OC and fill factor
than the DF-R molecule. Based on the given results, it
was supposed that all the newly presented molecules might prove themselves
to be better than the reference and thus might be of great interest
to experimentalists. Thus, they are suggested to be used to develop
proficient OSC devices with improved photovoltaic prospects in the
near future.