Properties of electronically excited states of four squaraine dyes and their complexes with fullerene C: A theoretical investigation.

Spectrochim Acta A Mol Biomol Spectrosc

School of Chemistry and Material Science, Shanxi Normal University, Linfen 041004, China.

Published: September 2017


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Solar cells sensitized by polypyridyl Ru(II) complexes exhibit relatively high efficiency, however those photo-sensitizers did not absorb the photons in the far-red and near-infrared region. At present, squaraine dyes have received considerable attention as their attractively intrinsic red light absorption and unusual high molar extinction coefficient. Here we applied density functional theory and time dependent density functional theory to investigate the properties of electronically excited states of four squaraine dyes and their complexes with fullerene C. The influences of different functionals, basis sets and solvent effects are evaluated. To understand the photophysical properties, the investigations are basing on a classification method which splits the squaraine dyes and their complexes with fullerene C into two units to characterize the intramolecular density distribution. We present the signatures of their electronically excited states which are characterized as local excitation or charge-transfer excitation. The relationship between open-circuit voltage and the number of intramolecular hydrogen bonds in squaraine dyes are discussed.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.saa.2017.04.086DOI Listing

Publication Analysis

Top Keywords

squaraine dyes
20
electronically excited
12
excited states
12
dyes complexes
12
complexes fullerene
12
properties electronically
8
states squaraine
8
density functional
8
functional theory
8
squaraine
5

Similar Publications

Squaraine dyes are promising for dye-sensitized solar cells (DSSCs) due to their strong absorption in the red and near-infrared regions. However, their ultrafast photophysical behavior remains poorly understood. Using two-dimensional electronic spectroscopy (2DES) and ab initio computations, we reveal signatures of a conical intersection (CI) governing excited-state dynamics in a prototypical squaraine dye.

View Article and Find Full Text PDF

Molecular excitons, which are excitations delocalized over multiple dyes in a wavelike manner, are of interest for a wide range of applications, including quantum information science. Numerous studies have templated a variety of synthetic dyes a DNA scaffold to induce dye aggregation to create molecular excitons upon photoexcitation. Dye aggregate optical properties are critically dependent on relative dye geometry and local environment; therefore, an understanding of dye-dye and DNA-dye interactions is critical for advancing toward more complex DNA-dye systems.

View Article and Find Full Text PDF

The current work focuses on elucidating the structural influence on the electronic properties and absorption spectra of a diverse series of functionalized BODIPY systems, inspired by squaraine dyes. In the current work, we considered two fusion frameworks of BODIPY-squaraine (bdp-sq) systems and functionalized them with selected polar groups (-X; -enX where en = ethenyl; X = NMe, PY, and PY). Utilizing state-of-the-art quadratic response theory (RI-CC2), we systematically examined how these fusion strategies and polar substitutions modulate their optical properties.

View Article and Find Full Text PDF

The stacking arrangement and associated interactions within the crystal packing of ten core-substituted squaraine (CSQ) dyes, which were symmetric dicyanovinyl (DCV) acceptor group-functionalized squaraine derivatives with distinct electron-rich side donor moieties containing various substituents, were assessed using computational methods. Out of the three sets, two contained indolenine and quinolinium donor moieties as side substitutions. In the first set, the halogen substituents on indolenine donor moieties (such as -Cl, -Br, and -I) exhibited monoclinic polymorphism, while the -F substituted one exhibited triclinic polymorphism.

View Article and Find Full Text PDF

Biotin is primarily taken up by cells through sodium-dependent multivitamin transporter, which is highly expressed in aggressive cancer cell lines, often at levels surpassing those of the folate receptor. This makes biotin an attractive ligand for tumor-targeted drug delivery. Building on this rationale, this study presents a series of six D-(+)-biotin-conjugated squaraine dyes derived from benzothiazole, indolenine, and benz[e]indole, with N-ethyl and N-hexyl chains.

View Article and Find Full Text PDF