Making and breaking of small water clusters: A combined quantum chemical and molecular dynamics approach

We present a combined quantum chemical and molecular dynamics study of cyclic and noncyclic water n-mers ([(H₂ O]_n , n = 2-6) at four different temperatures and showcase that the dynamics of small water clusters can reproduce the known properties of bulk water reasonably well. We investigate the making and breaking of the water clusters by computing the hydrogen bond strengths, average lifetimes, and relative stabilities, which are important to understand the complex solution dynamics. We compare the behavior of water clusters in the gas phase and in the solution phase as well as the variation in the properties as a function of cluster size and highlight the notably more interesting cluster dynamics of the water trimer when compared to the other water clusters. © 2019 Wiley Periodicals, Inc.