Theoretical Calculations of the Optical and Electronic Properties of Dithienosilole‐ and Dithiophene‐Based Donor Materials for Organic Solar Cells

Abstract

Six Acceptor‐Donor‐Acceptor (A−D−A) types molecules with dimethyl dithieno[3, 2‐b:2′,3′‐d]silole)−2,6‐diyl (DTS) (M1‐M3) and dimethyl cyclopenta [2, 1‐b;3,4‐b]‐dithiophene (CPDT) (M4‐M6) core flanged by different acceptor units through methylthiophene bridge are evaluated as donor materials for photovoltaic applications. The photovoltaic properties of M1‐M3 and M4‐M6 are compared with standard RaRc and Rb,Rd respectively. Geometry optimization was performed with CAM−B3LYP/6‐31G (d) level of theory. TD‐CAM−B3LYP has been employed for the estimation of excited state properties of the molecules. M1, M2, M3 and M4, M5, M6 symbolized suitable frontier molecular orbital's (FMO's) energy levels with broad absorption spectra. The electron withdrawing substituents impart red shift in absorption spectra along with good consistancy of designed donor molecules. Reorganization energies of donor molecules (M1‐M6) showed ideal properties of charge mobility. M1 and M4 illustrated lowest λe values as compared to λh, thus dictated that designed donor molecules are of good choice for their electron donating ability. Furthermore, M2 and M6 demonstrated shortest Eg of 3.7 and 3.72 eV among HOMO and LUMO energy levels.

Tuning the charge transfer and optoelectronic properties of tetrathiafulvalene based organic dye-sensitized solar cells: a theoretical approach

“…The partial density of states (PDOS) signies the relative contribution of a particular orbital or atom to the total DOS. [50][51][52][53] We have calculated the PDOS of our designed dyes to make a comparative study of their electronic properties with the frontier molecular orbitals (FMOs). The PDOSs of the designed dyes have been calculated and their respective spectral data are reported in Table S3 (in the ESI †).…”

Designing small organic non-fullerene acceptor molecules with diflorobenzene or quinoline core and dithiophene donor moiety through density functional theory

“…calculated the optical and electronic properties of newly designed dithieno[3,2-b:2′,3′-d]silole)2,6-diyl (DTS) based donor molecules through DFT and TD-DFT at CAM-B3LYP/6-31G (d) level of theory. FMOs energy, V oc , reorganization energies, excitation energy of the designed molecules were found better than the reference molecules 23 . Farhat et al .…”

Silver cluster doped graphyne (GY) with outstanding non-linear optical properties

“… 45 The more the crystalline material is, the less likely it is for charge transfer states to behave abnormally. 46 Dipole moment in gaseous ( μ g ), excited phase ( μ e ) and transition electric dipole moment (Δ μ ) is estimated using CAM-B3LYP/LANL2DZ functional for model 1 molecules while model 2 molecular systems are discussed using CAM-B3LYP functional with mixed basis set. Computed values of dipole moments are reviewed in Table 5 .…”

“…45 The more the crystalline material is, the less likely it is for charge transfer states to behave abnormally. 46 Dipole Fig. 15 EDDM images of pure GY as well as GY@Ag center -GY@3Ag center and 2GY as well as 2GY@Ag center -2GY@3Ag center .…”