Combined TD-DFT-SOS-CIS(D) Study of BOPHY Derivatives with Potential Application in Biosensing

Miguel-Armando Ponce-Vargas (1, 2) , Cloé Azarias (3) , Denis Jacquemin (4, 3) , Boris Le Guennic (1)

1 ISCR - Institut des Sciences Chimiques de Rennes
2 MSME - Laboratoire de Modélisation et Simulation Multi Echelle
3 CEISAM - Chimie Et Interdisciplinarité : Synthèse, Analyse, Modélisation
4 IUF - Institut universitaire de France

A set of 13 bis(difluoroboron)-1,2-bis((pyrrol-2-yl)methylene)hydrazine (BOPHY) dyes is studied through a hybrid time-dependent density functional theory (TD-DFT)-scaled opposite spin-configuration interaction singles with a double correction [SOS-CIS(D)] approach accounting for solvent effects, to shed light onto the structure-property relationships of these recently developed chromophores. In the first step, we calculate the absorption-fluorescence crossing points with refined TD-DFT models considering the influences of both vibrational and solvent contributions. We found that the systematic overestimation of the 0-0 energies is effectively reduced by combining polarizable continuum model-TD-DFT with a scaled opposite spin-configuration interaction singles with a double correction [SOS-CIS(D)]. Next, for a representative system, the vibrationally resolved spectrum within the harmonic approximation is computed on the basis of TD-DFT vibrational signatures and an excellent match with experiment is found. Finally, the influence of different lateral groups on the spectroscopic properties is rationalized by investigating charge transfer parameters and examining electronic density difference maps. It is found that one can tune the position of the absorption/emission maxima by a judicious choice of the lateral substituents or by using pi-extended segments. The largest absorption and emission wavelengths as well as the largest Stokes shifts are obtained for BOPHYs containing strong electron-donor dimethylaminophenyl groups attached to the alpha-positions of the pyrrole units through vinyl linkers, making these chromophores promising candidates for bioluminescence applications.

Domaines: Chimie théorique et/ou physique

Miguel-Armando Ponce-Vargas, Cloé Azarias, Denis Jacquemin, Boris Le Guennic. Combined TD-DFT-SOS-CIS(D) Study of BOPHY Derivatives with Potential Application in Biosensing. Journal of Physical Chemistry B, 2017, 121 (48), pp.10850-10858. ⟨10.1021/acs.jpcb.7b09698⟩. ⟨hal-01660897⟩