Among the nanosystems of greatest interest for our times, non-equilibrium alloys are intriguing for their original physical and chemical properties, that are exploitable in optics, nanomedicine, magnetism, catalysis and energy conversion.[1] Typically, non-equilibrium alloys contain elements with different reduction potentials, atomic sizes, crystalline packing in pure form, etc. and such a variety poses serious challenges for theoretical modelling as well as for synthesis and experimental investigation. The structure of many non-equilibrium multi-element compounds is characterized by high defectivity and strain, because atomic constituents are forced to organize in unconventional structures that cannot be simply described with the crystalline Bravais cells. Additionally, while materials are usually seen as well-defined objects in terms of composition, structure and shape, non-equilibrium alloys may have a 4-dimensional character, because they easily transform over time depending on the operating environment.[2]

In recent years, strong advancements were made in modelling of alloy nanocrystals, from their nucleation and growth stages up to their crystalline packing, electronic structure and related properties. Similarly, new techniques emerged for the realization of non-equilibrium alloys in a relatively easy and scalable fashion, such as the laser synthesis and processing of colloids, which permitted the investigation of new phenomena and advanced technological applications.[3,4]

Often, progresses in the field are allowed by the combination of theoretical outcomes with synthetic and experimental endeavours. [2,5,6,7,8]

Nonetheless, there is still a lot to understand about how to predict structural motifs arising in the metastable assembly of atomic constituents in real conditions. Accurate modelling and prediction of the physical properties and chemical characters enabled by the organization in non-equilibrium phases also remain challenging. Improving the theoretical description of nanocrystals formation during the laser-assisted synthesis is crucial as well for expanding the range of accessible nanoalloys.

This workshop will put together experts from the communities active in computational modelling of nanocrystals formation, structure and properties as well as from the laser synthesis and processing of non-equilibrium nanoalloys. The transversal competences collected in the workshop will allow to highlight the edge issues in modelling of:

- mechanisms of laser synthesis and processing of metal nanoparticles in liquids

- nucleation, growth and formation of non-equilibrium nanocrystals

- structural arrangements and morphologies in metastable alloy nanoparticles

- electronic structure of alloys

- physical properties of non-equilibrium nanoalloys compared to single metal nanoparticles (optical, magnetic, …)

- chemical reactivity and catalytic opportunities offered by nanoalloys

Bringing together a balanced group of participants from both the theoretical and experimental communities, the discussion about the key points of the experimental validation of theoretical predictions will be also favoured.

The emergence and exchange of ideas and constructive criticism will be stimulated by interactive platforms made available to participants throughout all the workshop.