Nairat, M. et al., Phys. Chem. Chem. Phys. 2017, 19, 14085 Time-Resolved Signatures Across the Intramolecular Response in Substituted Cyanine Dyes Muath Nairat Dantus Research Group 6/20/2017 Nairat, M. et al., Phys. Chem. Chem. Phys. 2017, 19, 14085

Cyanines structure & optical response Absorbance Guennic B. et al Acc. Chem. Res. 2015, 48, 530 Rosspeintner A. et al Annu. Rev. Phys. Chem. 2015, 64, 247

Applications of cyanines Solar energy capture Biomedical imaging Photodynamic therapy Zhao Y. et al Adv. Optical Mater. 2014, 2, 606 Ormond A. B. et al Materials. 2013, 6, 817 Fang C. et al Sci. Rep. 6, 21013

Unsubstituted cyanine: Cyanine’s electronic structures Unsubstituted cyanine: Substituted cyanine: Non-polar response Polar response

Synthesis

Optical properties Abs. blue shift Substituent Nucleophilicity Stokes shift Substituent Nucleophilicity

Experimental Setup

Negative Chirp TL Positive Chirp Red Blue

Chirp response

Ground state structure PBEα/6-311+G(3d,p) α=0.456

Ground state structure   NBO Charge on central C (e) mPi-IR806 0.463 mAn-IR806 0.410 mTF-IR806 0.387 IR806 0.057 PBEα/6-311+G(3d,p) α=0.456

Excited state potential energy surface CASSCF/6-31G(d)

Excited state potential energy surface

Excited state potential energy surface

Energy relaxation on PES MEP: minimum energy path

Thank you We are looking for students! Dantus Research Group nairatmu@chemistry.msu.edu We are looking for students! Dantus Research Group Nairat, M. et al., Phys. Chem. Chem. Phys. 2017, 19, 14085

Fluorescence Stimulated Emission