Gentle reminder TOMORROW: CMSP Seminar (Atomistic Simulation Seminar Series) 17 January, 15:00hrs, by Dr Angela Parise

[CMSP Seminars Secretariat]

------------------------------------------------------------------------
CMSP Seminar (Atomistic Simulation Seminar Series)
-------------------------------------------------------------------------

*Wednesday, 17 January 2024, 15:00 hrs*
*/Luigi Stasi Seminar Room (Leonardo Building, first floor)/*/
/
/Zoom registration link: 
https://zoom.us/meeting/register/tJwvd-GurTgjGtYpm4nYvlC4Oxj_ESD8k4V9
<https://zoom.us/meeting/register/tJwvd-GurTgjGtYpm4nYvlC4Oxj_ESD8k4V9> /

Speaker:*  Angela Parise * (CNR-IOM at SISSA)

Title: *First Principles Simulations of Biological Matter under Ionizing 
Radiations*

Abstract:

In-depth knowledge of the consequences of interaction of biomolecules 
with ionizing radiations is of fundamental importance for progress in 
medicine, radiotherapy and radioprotection as well as for addressing the 
panspermia hypothesis. The physicochemical events taking place during 
the first picoseconds after irradiation have so far escaped the scrutiny 
of researchers. Yet the plethora of vibrationally hot, electronically 
excited and highly reactive species formed upon irradiation is likely to 
trigger rich and non-conventional chemistry. For complex biostructures 
such as DNA or proteins irradiation could undergo currently unknown 
chemical damages with dramatic consequences for health. In the field of 
astrochemistry, ionizing radiations could have played a crucial role. 
The bombardment of the early Earth by comets that have captured organic 
rich interstellar icy grains is thought to have provided the molecular 
precursors at the origin of life on Earth. Such an assumption depends on 
the survival of these precursor under cosmic irradiations.

The propagation of time-dependent Kohn-Sham equations provides a mean to 
access the realm of attosecond electron dynamics [1]. Our group has 
implemented in deMon2k a RT-TD-DFT module [2]. In this contribution, I 
will present the details of this methodology. It will be shown how the 
physical sense of the method was validated by calculating the 
cross-section of the first ionization ofwater molecule in the gaseous 
phase and comparing it with the experimental data [3].Finally I will 
show first examples with deMon2k of effect induced by radiation to the 
electron cloud of bio-molecules [4].

*References*

[1]Runge, E.; Gross, E. K. U.,Phys.Rev.lettt. 1984, 52(12), 997-1000.

[2]Wu, X.; Teuler, J.-M.; Cailliez, F.; Clavaguéra, C.; Salahub, D. R.; 
de la Lande, A.,J. Chem. Theory Comput, 2017,13(9), 3985–4002.

[3]Parise, A.;Alvarez-Ibarra, A.; Wu , X.;Zhao, X.;Pilme, J.;de la 
Lande, A., J. Phys. Chem. Lett., 2018,9, 844−850.

[4] Alvarez-Ibarra, A.; Parise, A.; Hasnaoui, K.; de La Lande, A., Phys. 
Chem. Chem. Phys., 2020, 22, 7747-7758.

CMSP, Condensed Matter & Statistical Physics Section
http://www.ictp.it/research/cmsp.aspx

The Abdus Salam International Centre for Theoretical Physics
https://www.ictp.it/

    
----