“…Over the last few years, AMBER (used also for all the applications shown here) was substantially improved [ 21 ] (i) by refining the backbone and glycosidic torsion parameters [ 65 , 67 , 68 , 69 , 70 , 71 , 72 ]; (ii) by finely tuning the van der Waals parameters of nucleobase atoms [ 73 ]; (iii) by refining electrostatic, torsional, and van der Waals parameters of atoms other than those in (ii) [ 74 , 75 , 76 ]; (iv) by using the advanced water FFs, such as the TIP4P–D water model [ 77 ]; Although this may not be sufficient to significantly improve the performance of the FFs [ 21 ], the choice of water model affects accuracy in the prediction of experimental data such as NMR data [ 78 ]; and (v) by developing accurate nonbonded parameters for hydrogen bonding [ 79 , 80 ], which include induced polarization [ 64 ]. All of these improvements have succeeded in boosting RNA AMBER FF toward a predictive power approaching that of MD proteins [ 64 , 81 ].…”