Chemical Sensors : Modelling the Photophysics of Cation Detection by Organic Dyes
The increasing presence of various substances in our environment has brought abouta growing need for rapid emergence of new materials and devices in the quest forefficient and reliable chemical sensors. Massive technological progress have madeavailable an extensive range of technical tools to serve their development, accountingfor the requirements to be fulfilled (selectivity, quick response..). In this context,quantum chemistry methods provide a fundamental understanding of the processes atstake in the detection of chemical species and allow for rational design of sensingmaterials. Certain organic molecules can be extensively functionalised and thusconstitute an evident starting point owing to the tunability of their propertiesprovided by appropriate choice of structural modifications. The versatility of somechromophores associated to the selectivity offered by receptor units constitute theresearch playground for the development of ever better chemosensors.The present research aims at the rational development of chromoionophores for thecomplexation of cations, combining computational chemistry methods with basicspectroscopic characterisation. Using Density Functional Theory (DFT) and its timedependentextension (TD-DFT), two main aspects were treated, namely therelationship between molecular structure and optical properties of organicchromophores featuring valuable characteristics, and the complexation phenomenon.Photophysics of Zn2+ ion detection were more specifically studied, and recognitionwas demonstrated with both quantum-chemical calculations and experiments,accounting for the future integration of the chemical sensor in an optical fibre device.