In particular, we show that activated dinucleotides containing G and C monomers retain the highest percentage of Watson-Crick base pairing interactions with the template which can be both correlated to higher rates and fidelities of the primer extension reactions with these two RNA components. It is worth emphasising though that, when bound to the 5 ′ -end of the template, activated dinucleotides containing C more frequently adopt C2 ′ -endo ribose conformation which could hamper primer extension owing to longer O3 ′ • • • P distance between the adjacent nucleotide and the 3 ′ -end of the primer. Low rate and fidelity for the nonenzymatic template copying with A and U monomers is very well reflected by very low binding specificity of the dinucleotide intermediates containing these monomers in our simulations. In fact the ApAIpA and UpAIpU dinucleotides demonstrate a preference to fold into O-stacked and G-stacked structures of the imidazole bridged intermediate, which in most cases cannot bind specifically to the template. In addition, higher contribution of the C2 ′ -endo ribose conformation within these dinucleotides result in much less favorable (longer) O3 ′ • • • P distances.