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1. the electronic forces on the atomic scale driving chemical reactionsand building molecules of any imaginable complexity, whose action isexerted in lengths below 0.3 nanometers;

2. the intermediate forces (van der Waals) providing intermolecular po-tentials, governing phase states, and ultimately capable to shape solidsinto crystals, rods, flocks, etc. by molecular self-assembly with effectivelengths from 0.3 to some tens of nanometers [16, 17]; and

3. forces of capillary origin which appear on solid fragments when thesecan freely move in a liquid; since these forces are fundamentally propor-tional to the inverse of the characteristic length, they are particularlyimportant in the nano- and micrometric scales [7].

While the first originates from quantum mechanics and has an inherentlylarge variability depending on the nature of the element in question, thesecond and third forces stem from global free energies of analogous nature andmay yield structures showing fractality along several length scales. In thissense, crystals are the simplest paradigmatic cases where a basic structure canbe repeated along length scales spanning up to 9 or 10 orders of magnitude[18]. In particular, there are well established methods to grow nanocrystalsand nanostructures by molecular self-assembly in a controlled form fromsaturated atmospheres or solutions (e.g. [19, 20, 21, 22]) to yield functionalnanomaterials of enormous technological potential.

In general, structures formed by self-assembly differ significantly fromthose originated from spherical shapes, not only in appearance but also andmost importantly in functionality due to surface-to-volume differences andgeometrical features (shape) of individual particles or entities. The scientific

literature is rich in results illustrating these facts (see [9, 23, 24] and refer-ences therein for examples in many different areas) where the main driversare forces of the type (3) mentioned above, without entering in other surface-dependent complex molecular interactions. Moreover, in spite of the fact thatliquid fragmentation followed by capillarity may yield spherical droplets, sub-sequent steps on the scale provided by the droplet may lead to other shapesafter desolvation, curing, or freezing, and may involve crystallization. In re-ality, controlled liquid fragmentation in the form of droplets can be utilizedas an ideal compartmentalization step in the synthesis of functional materi-als and APIs: liquid droplets are nearly perfect cages providing sharp sizeand material limits by differential diffusivity, among other effects, without

using tangible barriers [25, 26, 27]. After desolvation or drying [28] (Fig. 2),

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