Structural correlations in liquid water are systematically examined using increasingly realistic theoretical models, including empirical rigid, empirical polarizable, empirical flexible with classical and quantum nuclei, and ab initio with classical nuclei at 300 and 353 K and quantum nuclei at 300 K. All models predict a significantly greater percentage of water molecules accepting two hydrogen bonds and a weaker temperature dependence of the hydrogen-bond angle than recent experimental reports suggest. (c) 2005 Elsevier B.V. All rights reserved.