ct9b00559_si_001.pdf (1.24 MB)
Unveiling the Photophysical Properties of Boron-dipyrromethene Dyes Using a New Accurate Excited State Coupled Cluster Method
journal contribution
posted on 2019-12-11, 19:03 authored by Romain Berraud-Pache, Frank Neese, Giovanni Bistoni, Róbert IzsákBoron-dipyrromethene (BODIPY) molecules form a class
of fluorescent
dyes known for their exceptional photoluminescence properties. Today,
they are used extensively in various applications from fluorescent
imaging to optoelectronics. The ease of altering the BODIPY core has
allowed scientists to synthesize dozens of analogues by exploring
chemical substitutions of various kinds or by increasing the length
of conjugated groups. However, predicting the impact of any chemical
change accurately is still a challenge, especially as most computational
methods fail to describe correctly the photophysical properties of
BODIPY derivatives. In this study, the recently developed coupled
cluster method called “domain-based local pair natural orbital
similarity transformed equation of motion-coupled cluster singles
and doubles” (DLPNO-STEOM-CCSD) is employed to compute the
lowest vertical excitation energies of more than 50 BODIPY molecules.
The method performs remarkably well yielding an accuracy of about
0.06 eV compared to the experimental absorption maxima. We also provide
an estimate to the error made by neglecting vibronic effects in the
computed spectra. The dyes selected for investigation here span a
large range of molecular sizes and chemical functionalities and are
embedded in solvents with different polarities. We have also investigated
if the method is able to correctly reproduce the impact of a single
chemical modification on the absorption energy. To characterize the
method in more specific terms, we have studied four large BODIPY analogues
used in real-life applications due to their interesting chemical properties.
These examples should illustrate the capacity of the DLPNO-STEOM-CCSD
procedure to become a method of choice for the study of photophysical
properties of medium to large organic compounds.