Thrombin-mediated proteolytic cleavage in the central E domain of fibrinogen results in the release of fibrinopeptides A and B from the N-terminal regions of the α and β chains of fibrinogen, respectively, leading to the formation of a soluble fibrin monomer (Ni et al. 1989; Pechik I et al., 2006; Riedel T et al., 2011). The cleavage unmasks four binding sites in the E domain of monomeric fibrin allowing binding to the C-terminal region of the D domain from other fibrin monomers (Everse SJ et al., 1998, 1999; Doolittle RF 2003; Litvinov RI et al., 2005, 2007). Fibrin monomers rapidly and spontaneously associate into large multimers, which elongate into protofibrils that later aggregate to form fibers, creating a three-dimensional network (Laudano AP and Doolittelle RF 1980; Huang L et al., 2014; Zhmurov A et al., 2016; Litvinov RI et al., 2018; Asquith NL et al., 2022; Pietsch K et al. 2023; reviewed by Litvinov RI et al., 2021). The structural organization is essential for the mechanical properties of the clot (Litvinov RI & Weisel JW 2017; Risman RA et al., 2024; reviewed by Feller T et al., 2022). The process of multimerization, and the range of multimer structures that can form in vivo and in vitro, have been studied in detail (Doolittle RF 1984, 2003; Huang L et al., 2014; Zhmurov A et al., 2018; Litvinov RI & Weisel JW 2017; Risman RA et al., 2024). Here, multimer size has arbitrarily been set to three fibrin monomers.