2
EINLADUNG
ZUM PHYSIKALISCHEN KOLLOQUIUM
AM MONTAG, DEM 05.05.2008 UM 17.15 UHR
HS 46/270
ES SPRICHT: Prof. Dr. R. Bini
LENS and Dipartimento di Chimica dell'Università di Firenze
Thema:
High-pressure chemistry of simple molecules:
the solid state reactivity through a microscope
An impressive growing interest in high pressure studies was observed in the last years in different research fields ranging from fundamental physics, chemistry, biology to geo- and space- sciences. This is probably ascribable to the availability of a versatile device, the Diamond Anvil Cell (DAC), which allowed the investigation of different kind of samples by using an incredible variety of probing techniques. As far as the chemistry is concerned, high-pressure methods have been historically confined to the Kbar range (1 Kbar ~ 0.1 GPa) while the DAC employment allows the exploration of stability boundaries in the Mbar range thus making feasible also the study of the stability of the simplest molecular systems. Remarkable advances have been made in the synthesis and in the characterization of new classes of materials made by light elements starting, quite often, from very simple molecules. In addition, surprising transformations for simple molecules like O2 or CO2 have been found, while polymers and amorphous products where synthesized by the simplest hydrocarbons avoiding catalysts or initiators. The careful characterization of the products and the kinetics of the reactions under investigation combined to the possibility to control all the variables ruling the reactivity of these pure systems (pressure, temperature and wavelength), allowed to get insight into the mechanisms regulating the reactivity at the microscopic level. The role of the lattice phonons in driving and assisting chemical reactions in the crystal phase, the modification of the electronic structure due to the compression and the employment of specific wavelength to trigger selective chemical reactions are some of the most enlightening results obtained by our group and appear as a promising and unavoidable background for designing tailor-made solid state reactions involving simple molecules.
Der Gast wird betreut von Prof. Dr. H.-J. Jodl
GÄSTE SIND HERZLICH WILLKOMMEN.
KAFFEEAUSSCHANK AB 17.00 UHR
Kaiserslautern, den 22.04.2008