The Dynamics lab at IESL-FORTH uses light (especially lasers) to study Chemistry. Current projects are briefly discussed below.

 

Research Topics

We have investigated the dynamics of HBr, CH3Br and CH3I when excited in the 7-10 eV region. The interactions between Rydberg, ion pair and ionic states of the molecules affect the photoproducts significantly. For example, while excitation energy in CH3Br is distributed in electronic and ro-vibrational excitation of the CH3 fragment, in CH3I all excitation energy is channeled into electronic excitation of the I fragment.
Our CH3I work was featured as a PCCP 2020 Hot Article and Editor’s choice in 2020.

We published the first tunable ns PECD data using a tunable ns laser to ionize fenchone enantiomers in the 375-420 nm region in order to see if PECD changes with vibrational level excitation. Our data suggest that is doesn’t, but further investigation in different regions and molecules is needed to confirm. 

The aim is to characterize the important factors that influence the kinetics of elementary reactions at surfaces, e.g. the chemical nature of the catalyst and the geometry of the active site (stereodynamics). We chose elementary reactions involving C, H, O, N, as these are important in many key industries, such as the methane reforming, syngas, fuel cells, Fischer-Tropsch synthesis and the Haber-Bosch process.  Our strategy is that of a “bottom-up” approach to catalysis, i.e., building and understanding complex heterogeneous chemical catalysis, from the site-specific kinetics of the elementary building block reactions.  Our measurements, will serve for benchmarking first principles calculations of reaction rates in surface chemistry.  Our methodology measures the kinetics in the ms regime with temperatures in the 200 to 1000 K range, i.e, conditions more relevant to industrial conditions.

Our Time-Resolved Electron Diffractometer is currently under construction. We use the term “time-resolved” and not "ultrafast" as we plan to use both ultrashort (500fs) and nanosecond laser pulses, in order to investigate phenomena ranging from a few ps to μs. We envision first experiments in “dark” reactions in gas phase with a plan to expand in solid state studies as soon as technically possible.

We combine machine learning analysis methods and spectroscopic data ( UV-NIR absorption, fluorescence, FT-IR) of pure fossil fuels (different types of gasoline and diesel) and adulterants (solvents, lubricants, lubricants waste oils) and their mixtures aiming to develop a system that will detect fuel adulteration spectroscopically in a reliable, cheap and user-friendly fashion. The work is funded under project "APOFASH".
This work is part of a general research direction aiming to improve how we use light and spectroscopy to detect molecules of choice in a chemical mixture.

Development of an optical spectroscopy system prototype for fuel adulteration detection
Detecting chirality in mixtures using nanosecond photoelectron circular dichroism
S. T. Ranecky, G. B. Park, P. C. Samartzis, I. C. Giannakidis, D. Schwarzer, A. Senftleben, T. Baumert, T. Schäfer
Phys. Chem. Chem. Phys., Volume:24, Page:2758, Year:2022, DOI:doi.org/10.1039/D1CP05468F
Following the Microscopic Pathway to Adsorption through Chemisorption and Physisorption Wells
D. Borodin, I. Rahinov, P. R. Shirhatti, M. Huang, A. Kandratsenka, D. J. Auerbach, T. L. Zhong, H. Guo, D. Schwarzer, T. N. Kitsopoulos, A. M. Wodtke
Science, Volume:369, Page:1461, Year:2020, DOI:doi.org/10.1126/science.abc9581
High-resolution resonance-enhanced multiphoton photoelectron circular dichroism
A. Kastner, G. Koumarianou, P. Glodic, P. C. Samartzis, N. Ladda, S. T. Ranecky, T. Ring, S. Vasudevan, C. Witte, H. Braun, H. G. Lee, A. Senftleben, R. Berger, G. B. Park, T. Schäfer, T. Baumert
Phys. Chem. Chem. Phys., Volume:22, Page:7404, Year:2020, DOI:doi.org/10.1039/D0CP00470G
Formation of highly excited iodine atoms from multiphoton excitation of CH3I
K. Matthıasson, G. Koumarianou, M. X. Jiang, P. Glodic, P. C. Samartzis, A. Kvaran
Phys. Chem. Chem. Phys. , Volume:22, Page:4984, Year:2020, DOI:doi.org/10.1039/C9CP06242D
The Kinetics of Elementary Thermal Reactions in Heterogeneous Catalysis
G.B. Park, T. N. Kitsopoulos, D. Borodin, K. Golibrzuch, J. Neugebohren, D. J. Auerbach, C. T. Campbell, A. M. Wodtke
Nature Reviews Chemistry, Volume:3, Page:723, Year:2019, DOI:doi.org/10.1038/s41570-019-0138-7
Velocity-resolved kinetics of site-specific carbon monoxide oxidation on platinum surfaces
J. Neugebohren, D. Borodin, H. W. Hahn, J. Altschäffel, A. Kandratsenka, D. J. Auerbach, C. T. Campbell, D. Schwarzer, D. J. Harding, A. M. Wodtke, T. N. Kitsopoulos
Nature, Volume:558, Page:280, Year:2018, DOI:doi.org/10.1038/s41586-018-0188-x
Spin-Polarized Hydrogen Atoms from Molecular Photodissociation
11. T.P. Rakitzis, P.C. Samartzis, R.L. Toomes, T.N. Kitsopoulos, Alex Brown, G.G. Balint-Kurti, O.S. Vasyutinskii, J.A. Beswick
Science, Volume:300, Page:1936, Year:2003, DOI:doi.org/10.1126/science.1084809
Slice imaging: A new approach to ion imaging and velocity mapping
C.R. Gebhardt, T.P. Rakitzis, P.C. Samartzis, V. Ladopoulos, T.N. Kitsopoulos
Rev. Sci. Instrum. , Volume:72, Issue:10, Page:3848, Year:2001, DOI:doi.org/10.1063/1.1403010

Heads

Prof. Kitsopoulos Theofanis
University Faculty Member
Dr. Samartzis Petros
Principal Researcher

Technical Staff

Mr. Englezis Apostolos
Technical Scientist
Mr. Lamprakis Yannis
Technical Scientist

Students

Mr. Giannakidis Giannis
M.Sc. student
Mr. Fragkoulis Nikolaos
Ph.D. student

Alumni

Ms. Afentaki Aggeliki
M.Sc. student
Mr. Hatzakis Alexandros
Undergraduate trainee
Ms. Marinopoulou Dimitra
Undergraduate trainee
Ms. Podara Christina
Undergraduate trainee
Mr. Reppas Konstantinos
Undergraduate trainee
Ms. Koumarianou Greta
M.Sc. student
Mr. Glodic Pavle
Ph.D. student
Mr. Kartakoulis Andreas
Ph.D. student
Mr. Velegrakis Aris
Technician