Date: 4 September 2018 (Tuesday)

Time: 3:00 - 4:00pm

Venue: B5209, Yeung Kin Man Academic Building

After photoexcitation, transition metal complexes can undergo a plethora of interconnected relaxation processes, which compete to each other and are controlled by the subtle interplay of electronic and geometrical rearrangements that take place during the excited state deactivation dynamics. Intrinsic factors such as e.g., i) the spin and character of the electronically ES involved in the process and ii) the energetic alignment and effective couplings between these states, do play a protagonist role in determining the preferred deactivation channels. Extrinsic factors, such as e.g., temperature, pressure, excitation wavelength and environmental effects can often strongly modify the outcome of the photochemical processes. As kinetic control is always at play, only the fastest processes among all possible deactivation channels are generally observed. [1] In this contribution, I present some of our recent works rationalizing the photochemical properties of Ir(III) complexes. Particularly, we have recently developed a general approach to compute their photoluminescence efficiencies, which is based on the use of state-of-the-art quantum chemical calculations along with excited state decay rate theories and kinetic modelling.[2] The photostability of Ir(III) complexes upon OLED operation has

also been investigated.[3]

[1] D. Escudero, D. Jacquemin, Dalton Trans., 2015, 44, 8346.

[2] a) X. Zhang, D. Jacquemin, Q. Peng, Z. Shuai, D. Escudero. J. Phys. Chem. C, 2018, 122, 6340; 
      b) D. Escudero, Chem. Sci., 2016, 7, 1262.

[3] D. Escudero, Chem. Sci., 2017, 8, 7844.

Biography

Daniel ESCUDERO studied chemistry at the University of the Balearic Islands (Spain), where he received his M.Sc. (2007). He moved to the Friedrich-Schiller University (Jena, Germany) to do his PhD under the supervision of Prof. Leticia González. His PhD work focused on the computation of spectroscopic and photochemical properties of transition metal complexes employing ab initio quantum chemistry and chemical dynamics methods. Following his PhD, in November 2011 he moved to the group of Prof. Walter Thiel at the Max-Planck-Institut für Kohlenforschung (Mülheim an der Ruhr, Germany) as a postdoctoral researcher. In this postdoctoral period he started new avenues of research, including the application of hybrid approaches - such as the combined QM/MM methods- to larger systems and biocatalysis. Concurrently, he continued working actively in the field of excited states, focusing on the study of Organic light-emitting diodes (OLEDs). Since November 2014 he was a postdoctoral researcher in the MARCHES project led by Prof. Denis Jacquemin at the University of Nantes. He is currently a Research fellow at CEISAM in University of Nantes. He is appointed Research Assistant BOFZAP Professor at the Chemistry Department at KU Leuven (Belgium) from October 2018.

Enquiry:

Department of Materials Science and Engineering

Email: mse@cityu.edu.hk

Tel: 3442 2985