Periodic Reporting for period 1 - MAMBA (Materials irradiation: from basics to applications)
Berichtszeitraum: 2023-11-01 bis 2025-10-31
Quite frequently matter is subject to irradiation. Think of electronic devices in space, radiotherapies, materials in the nuclear industry, or radiation detectors. A common denominator is that radiation brings matter out of equilibrium, sometimes quite dramatically, leading to physical, chemical, and biological phenomena at all scales, from attosecond and nanometer deposition to meters and days at the engineering or biological scale, where macroscopic phenomena like failure, fracture, or death can occur. Whether it is avoiding or mitigating damage or harnessing the effects of radiation, it is crucial to understand the fundamental mechanisms of material response to intense and fast energy deposition.
The research aim of MAMBA is to advance our understanding of material response to irradiation and to apply it to tailor and control the properties of materials exposed to intense radiation environments. We selected five case studies lying at the frontier of knowledge, and spanning applications in diverse, although connected, fields: space electronics, photovoltaic cells, radiation-resistant nanostructures, radiation detectors, proton radiotherapy, and radiolytic hydrogen generation. These topics are being addressed through a combination of common experimental and modelling techniques. This commonality allows for cross-pollination between themes and for implementing a rich training program.
The research aim of MAMBA is to advance our understanding of material response to irradiation and to apply it to tailor and control the properties of materials exposed to intense radiation environments. We selected five case studies lying at the frontier of knowledge, and spanning applications in diverse, although connected, fields: space electronics, photovoltaic cells, radiation-resistant nanostructures, radiation detectors, proton radiotherapy, and radiolytic hydrogen generation. These topics are being addressed through a combination of common experimental and modelling techniques. This commonality allows for cross-pollination between themes and for implementing a rich training program.
A1.1: A list of materials and defects to be studied in parallel by experimental and by first-principles modelling was defined, together with research schemas to achieve a meaningful comparison between theory and experiment. A practical application to Ti defects in Si was carried out (WP1).
A2.1: PbS, CdS, CdTe, and ITO thin films were deposited using the RF Sputtering technique by varying the incident power, Ar pressure, and deposition times. All were characterized by XRD, and specifically, the PbS films were characterized by AFM, UV-Vis with diffuse reflectance, Raman, and SEM. An unexpected columnar growth was observed leading to a quantum confinement phenomenon. PbS films were then deposited onto ITO-glass,ad further were irradiated with protons at 2 MeV. These were subsequently characterized by in situ UV-Vis and Raman Spectroscopy, where the influence of the radiation on the structural, optical, and vibrational properties was analyzed (WP2).
A2.2: Ultrafast X-ray and swift heavy ion irradiation of CdS was studied using a multiscale Monte Carlo/TTM-MD approach. An article for X-ray irradiation was already published and two others are under review (in ArXiv) (WP2).
A3.1: Metallic alloy nanoparticles were synthesized in solution through colloidal chemistry and pulsed laser ablation. This was done for Ag, Au, Pt, Pd, Ir, Ru, and Rh, for bimetallic alloys (core-shell), multi-metallic alloys, and Hithe Entropy Alloys (HEA) made of up to five metals. These systems were then characterized via optical absorption, EDX mapping and TEM experiments. Clusters of different types of nanoparticles (e.g. nanorods and nanospheres) and different types of multi-metallic nanostructures were irradiated with femtosecond laser pulses for varying laser fluence. Single-metal Au and Ag nanoparticles were irradiated with swift heavy ions (SHI) Br or I at CMAM in Madrid, while conducting in situ optical absorption measurements with polarized light and computational analysis to characterize the elongation kinetics as a function of ion fluence via surface plasmon resonances (WP3).
A4.1: Hybrid DFT calculations of the location, defect energy levels, and thermodynamic transition levels of excess electrons and holes in LiF doped with Mg and Ti, and Al2O3 doped with C, were conducted and published (WP4)
A4.2: The propagation of classical electrons in condensed phases via rt-TDDFT was implemented in code QB@ll developed by A. A. Correa at LLNL (USA), and used to study the interaction of classical electrons with LiF, specifically the electronic stopping power (WP4)
A4.3: the response of the dosimetric materials LiF, Gafchromic film and Magic-f gel exposed to different ionizing radiation beams was determined experimentally and compared against calculations. Article published (WP4)
A5.1: Theoretical distorted-wave (CDW-EIS) and semi-empirical cross sections for the impact of swift protons, electrons, and heavy ions on molecules of biological interest (water, DNA and RNA bases) were calculated and implemented in Monte Carlo codes (MDM, MDM-Ion and LQD) to determine stopping power, W-values, and particle ranges in biological media. Article published (WP5)
A5.2: The influence of the cross sections on cell survival was evaluated by introducing improved cross sections into Monte Carlo simulations and also evaluating the relevance of considering electron Auger emission in the biological parameters in the framework of the NanOx Biophysical model (WP5).
A5.3: Bond breaking events post-Dissociative Electron Attachment (DEA) were studied via DFT calculations of the gas-phase and solvated deoxycytidine phosphate nucleotide. Dissociation energies and barriers were computed via geometry optimization, to elucidate a change of behavior upon solvation (WP5).
A5.4: An extensive literature review on the effects of ionizing radiation on blood was carried out within the UNR–INFN collaboration, resulting in a comprehensive review article recently published in Biophys. Rev. In parallel, irradiation of blood samples with different radiation qualities—gamma rays, X-rays, and therapeutic electron beams was carried out at UNR (WP5)
A5.5: A novel microdosimetric biophysical model, referred to as the Continuous Microdosimetric Photon Isoeffective Dose model (COMPHID), was developed to describe proton biological effectiveness based on microdosimetric spectra. The model parameters were derived from microdosimetric and radiobiological experiments performed at the Trento Proton Therapy Center (WP5).
A6.1: DFT calculations of bulk and surface structure and surface energy of three representative oxides, ZrO2 , Cu2O, and CuO, were carried out with the Quantum-espresso package. (WP6).
A6.2: DFT calculations of the structure and bonding energy of the oxide-water interface were carried out for ZrO2/water. The calculations were used to develop a machine-learned (ML) potential for the ZrO2/water system. The ML potential was then used to study the interfacial structure of the system, including water dissociation and ZrOH moieties at the interface (WP6).
A6.3: Many-body perturbation theory calculations were conducted and the exciton wavefunction and binding energies were obtained for bulk ZrO2 in its three different crystallographic structures, by solving the GW and the Bethe-Salpeter equations. This was done with three different codes: ABINIT, VASP, and YAMBO (WP6)
A2.1: PbS, CdS, CdTe, and ITO thin films were deposited using the RF Sputtering technique by varying the incident power, Ar pressure, and deposition times. All were characterized by XRD, and specifically, the PbS films were characterized by AFM, UV-Vis with diffuse reflectance, Raman, and SEM. An unexpected columnar growth was observed leading to a quantum confinement phenomenon. PbS films were then deposited onto ITO-glass,ad further were irradiated with protons at 2 MeV. These were subsequently characterized by in situ UV-Vis and Raman Spectroscopy, where the influence of the radiation on the structural, optical, and vibrational properties was analyzed (WP2).
A2.2: Ultrafast X-ray and swift heavy ion irradiation of CdS was studied using a multiscale Monte Carlo/TTM-MD approach. An article for X-ray irradiation was already published and two others are under review (in ArXiv) (WP2).
A3.1: Metallic alloy nanoparticles were synthesized in solution through colloidal chemistry and pulsed laser ablation. This was done for Ag, Au, Pt, Pd, Ir, Ru, and Rh, for bimetallic alloys (core-shell), multi-metallic alloys, and Hithe Entropy Alloys (HEA) made of up to five metals. These systems were then characterized via optical absorption, EDX mapping and TEM experiments. Clusters of different types of nanoparticles (e.g. nanorods and nanospheres) and different types of multi-metallic nanostructures were irradiated with femtosecond laser pulses for varying laser fluence. Single-metal Au and Ag nanoparticles were irradiated with swift heavy ions (SHI) Br or I at CMAM in Madrid, while conducting in situ optical absorption measurements with polarized light and computational analysis to characterize the elongation kinetics as a function of ion fluence via surface plasmon resonances (WP3).
A4.1: Hybrid DFT calculations of the location, defect energy levels, and thermodynamic transition levels of excess electrons and holes in LiF doped with Mg and Ti, and Al2O3 doped with C, were conducted and published (WP4)
A4.2: The propagation of classical electrons in condensed phases via rt-TDDFT was implemented in code QB@ll developed by A. A. Correa at LLNL (USA), and used to study the interaction of classical electrons with LiF, specifically the electronic stopping power (WP4)
A4.3: the response of the dosimetric materials LiF, Gafchromic film and Magic-f gel exposed to different ionizing radiation beams was determined experimentally and compared against calculations. Article published (WP4)
A5.1: Theoretical distorted-wave (CDW-EIS) and semi-empirical cross sections for the impact of swift protons, electrons, and heavy ions on molecules of biological interest (water, DNA and RNA bases) were calculated and implemented in Monte Carlo codes (MDM, MDM-Ion and LQD) to determine stopping power, W-values, and particle ranges in biological media. Article published (WP5)
A5.2: The influence of the cross sections on cell survival was evaluated by introducing improved cross sections into Monte Carlo simulations and also evaluating the relevance of considering electron Auger emission in the biological parameters in the framework of the NanOx Biophysical model (WP5).
A5.3: Bond breaking events post-Dissociative Electron Attachment (DEA) were studied via DFT calculations of the gas-phase and solvated deoxycytidine phosphate nucleotide. Dissociation energies and barriers were computed via geometry optimization, to elucidate a change of behavior upon solvation (WP5).
A5.4: An extensive literature review on the effects of ionizing radiation on blood was carried out within the UNR–INFN collaboration, resulting in a comprehensive review article recently published in Biophys. Rev. In parallel, irradiation of blood samples with different radiation qualities—gamma rays, X-rays, and therapeutic electron beams was carried out at UNR (WP5)
A5.5: A novel microdosimetric biophysical model, referred to as the Continuous Microdosimetric Photon Isoeffective Dose model (COMPHID), was developed to describe proton biological effectiveness based on microdosimetric spectra. The model parameters were derived from microdosimetric and radiobiological experiments performed at the Trento Proton Therapy Center (WP5).
A6.1: DFT calculations of bulk and surface structure and surface energy of three representative oxides, ZrO2 , Cu2O, and CuO, were carried out with the Quantum-espresso package. (WP6).
A6.2: DFT calculations of the structure and bonding energy of the oxide-water interface were carried out for ZrO2/water. The calculations were used to develop a machine-learned (ML) potential for the ZrO2/water system. The ML potential was then used to study the interfacial structure of the system, including water dissociation and ZrOH moieties at the interface (WP6).
A6.3: Many-body perturbation theory calculations were conducted and the exciton wavefunction and binding energies were obtained for bulk ZrO2 in its three different crystallographic structures, by solving the GW and the Bethe-Salpeter equations. This was done with three different codes: ABINIT, VASP, and YAMBO (WP6)
1) A methodology to compute electronic stopping power for classical electrons has been developed and applied to LiF, with further applications to water under development. This is a completely new approach with a significant potential for future research and applications in radiotherapy, radiation detectors, and other fields.
2) A catalogue of multi-metallic nanoparticles, of the highe entropy allow type, was produced by colloidal synthesis and laser ablation. There is potential for these nanoparticles to be used as radiation-resistant materials for intense radiation environments, for example those in the first wall of future nuclear fusion reactors.
2) A catalogue of multi-metallic nanoparticles, of the highe entropy allow type, was produced by colloidal synthesis and laser ablation. There is potential for these nanoparticles to be used as radiation-resistant materials for intense radiation environments, for example those in the first wall of future nuclear fusion reactors.