<i>Ab Initio</i> Simulation of Liquid Water\nwithout Artificial High Temperature

Comprehending\nthe structure and dynamics of water is crucial in\nvarious fields, such as water desalination, ion separation, electrocatalysis,\nand biochemical processes. While reported works show that the <i>ab initio</i> molecular dynamics (AIMD) can accurately portray\nwater’s structure, the artificial high temperature (AHT) from\n120 to 30 K is needed to mimic the quantum nature of hydrogen-bond\nnetwork from GGA, metaGGA to hybrid functionals. The AHT proves to\nbe an inadequate approach for systems involving aqueous multiphase\nmixtures, such as water–solid interfaces and aqueous solutions.\nThis is due to the activation of additional phonons in other phases,\nwhich can lead to an overestimation of the dynamics of nearby water\nmolecules. In this work, we find that the regularized SCAN (rSCAN)\nfunctional effectively captures both the structure and dynamics of\nliquid water at ambient conditions without AHT. Moreover, rSCAN closely\nmatches experimental results for the hydration structures of alkali,\nalkali earth, and halide ions. We anticipate that the versatile and\naccurate rSCAN functional will emerge as a key tool based on <i>ab initio</i> simulation for investigating chemical processes\nin aqueous environments.