Thesis Defense Jakub Širůček – Lundi 26 Octobre 2026

This thesis is supervised by Prof. Denis JACQUEMIN – CEISAM – Nantes Université and Dr. Boris LE GUENNIC – CNRS/ISCR – Université de Rennes

Examining Committee :
➖ Prof. Benoît CHAMPAGNE – Laboratoire de Chimie Théorique – Université de Namur – Reviewer
➖ Dr. Ilaria CIOFINI – CNRS/Chimie ParisTech – Reviewer
➖ Dr. Miquel HUIX-ROTLLANT – CNRS/Institut de Chimie Radicalaire de Marseille – Examiner
➖ Dr. Alexandra VIEL – CNRS/IPR – Université de Rennes – Examiner

[📄 ABSTRACT] Optical limiting materials have emerged as an efficient means of protecting human eyes against intense radiation, e.g., pilots’ vision against malicious laser dazzling. Ideally, such materials retain transparency at low fluence while absorbing part of the incoming radiation at high fluence. Efficient design of optical limiting molecules typically requires intense excited-state absorption (ESA). To theoretically describe ESA using computational chemistry, one is interested in its intensity, described by ESA oscillator strengths ($f_{ESA}$), and the positions of ESA peaks, corresponding to ESA energy gaps ($E_{ESA}$). Both can be obtained efficiently using quadratic and linear response theory, notably within TD-DFT. In this thesis, I developed a cost-effective methodology for ab initio calculations of $f_{ESA}$ and $E_{ESA}$. I established accurate $f_{ESA}$ values using QR-CC3 to assess less expensive methods, notably QR-TD-DFT. Following this benchmark, I implemented and analyzed an additional unrelaxed LR-TD-DFT approximation, allowing solvent effects to be introduced via LR-PCM and $cLR^{2}$. These results allowed me to validate ESA energy gaps and oscillator strengths against transient spectroscopy and ultimately derive design rules for intense ESA in azulene derivatives for optical limiting.