The simulation of the excited state properties of complex and realistic systems represents a wide field at the forefront of research. Such systems include, e.g., surfaces, biomolecules, nanostructured materials, and potentially any combination of them. In this realm the present NFFA installation provides access to the most up-to-date and efficient ab-initio codes that, in a fully parameter-free way, make possible to describe a wealth of equilibrium and out-of- equilibrium properties.
Excited state properties in static conditions:
Excited state properties in metastable equilibrium conditions are crucial for the understanding of the quantum-mechanical properties of the materials. The related observables can give access to the single-particle energy levels, optical excitations and much more:
Out-of-Equilibrium / Dynamical excited state properties:
The out-of-equilibrium dynamics describes how the system responds to external stimuli and evolves from one configuration to the other. Several dynamical processes are possible, ranging from those involving the motion of atoms and molecules (occurring on the time-scale of the picosecond) to those involving the motion of electrons, occurring on very short time- scales, ranging from femto to even atto-seconds. Both timescales can be addressed by the codes developed by, and available to, the NFFA theory installation. The offer presently includes calculation of a wealth of dynamical excited state properties such as:
Neutral excitations: time-resolved transient absorption, reflectivity and photoluminescence;
Time dependent density functional theory calculations, GW many perturbation theory calculations
ICN2
Spain
SIESTA
Time Dependent Density Functional Theory
Real time dynamics of excited states
Coupled electron-nuclear dynamics in excited states
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no
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0
CNR-ISM
Italy
Yambo
Yambo is a general purpose tool for theoretical spectroscopy. The code can perform several kind of calculations (https://www.yambo-code.eu/about/). Most of these methods fall in the realm of excited state calculations: quasi-particle properties, optical absorption, electron energy loss. Yambo can include the effect of the electron-hole attraction (excitons) as well as electron-phonon interaction (finite temperature effects) and more.
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no
na
0
no
JÜLICH
Germany
FLEUR
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na
no
na
0
UMIL
Italy
YAMBO
Excited state properties of bulk systems, surfaces, molecules, using many-body methods (https://www.yambo-code.eu/about/). <https://www.yambo-code.eu/about/).
Optical absorption spectra, electron energy loss, Kerr effect, circular dichroism, excitonic effects, electron-phonon interaction.
na
no
na
0
UMIL
Italy
OCTOPUS
Linear and non linear optical response; pump and probe simulations on nanoalloys (Au and Ag based).
Up to hundreds of atoms.
This technique offers the possibility of simulating structural and electronic properties based on the electronic ground state, including electronic charge analysis, energetics of formation, structural and vibrational properties; IR, Raman, EPR, NMR, core-level XAS & XPS, STM & AFM.
SAXS is a non-destructive and versatile method to study the nanoscale structure of any type of material (solid, liquid, aerosols) ranging from new nanocomposites to biological macromolecules. Averaged particle sizes, shapes and distributions, porosity, degree of crystallinity and electron density maps with nanometer precision can be obtained.
VUV/UV/Vis/NIR spectroscopy is the measurement of the attenuation of a beam of light after it passes through a sample or after reflection from a sample surface. It is useful to characterize absorption, transmission, and reflectivity of a variety of technologically important materials, such as gases, film, pigments, coatings, windows, and filters.
