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A variety of attractive short‐range forces, such as covalent bonds, dipolar interactions, hydrogen bond, and donor–acceptor interaction, are used to build both complex molecules and crystals (Desiraju 1995; Moulton and Zaworotko 2001). In this regard, hydrogen bonds allow the organization of nanorods in linear chains (Thomas et al. 2004; Guo and Dong 2011). Besides, there are reports in the literature on DNA as a linker for assembling particles selectively and reversibly (Alivisatos et al. 1996; Mirkin et al. 1996).

Finally, other examples relate to dipole–dipole interactions between groups of photoisomerizable surfaces allowing rapid assembly and disassembly of ordered nanoparticles (Steiner 2002).

In this context, these interactions give rise to interparticle potentials that allow the organization in highly ordered structures. These forces depend on the number of individual bonds (covalent or noncovalent) and the binding force characteristic of the molecular interaction. While the interactions can be quite weak, the forces between suitably functionalized surfaces can be quite strong due to the interaction of many molecular groups. These interactions show a variable length from nanometers to angstroms (molecular size λ) and depend on the specific interacting molecules. Therefore, the interactions will not take place based on the distance, but in contrast, they will be dependent on the λ factor as in an on–off mechanism.

In this respect, the hydrogen bonds, as well as the polar interactions, are electrostatic (Abe et al. 1976; Steiner 2002) by allowing the nanoparticles (Johnson et al. 1997; Boal et al. 2000; Kimura et al. 2004) and nanorods (Thomas et al. 2004; Sun et al. 2008; Guo and Dong 2011) assembly.

The hydrogen bonding is shown to induce the aggregation of metal nanoparticles functionalized with hydrogen bonding ligands where the degree of aggregation and order depends on the strength of the individual hydrogen bonds formed. Therefore, Nonappa and Ikkala (2018) in their work, provide an example, how the anisotropic colloidal interactions of H‐bonding nanoparticles can direct colloidal self‐assemblies of nanorods. Recently, Yue et al. (2015) described the formation of ZnO nanoparticle chains and demonstrated the importance of the nanoparticle–solvent interactions, notably, the hydrogen bond, in obtaining the stability of the chain structure by using different simulations. Therefore, the Molecular Dynamic (MD) confirmed the role of hydrogen bonding in stabilizing the chain‐like structure, and Dissipative Particle Dynamics (DPD) simulations revealed the importance of nanoparticle–solvent interactions in guiding anisotropic self‐assembly.