ISOCHORIC DIFFERENTIAL SCATTERING FUNCTIONS IN LIQUID WATER - THE 5TH NEIGHBOR AS A NETWORK DEFECT

We show that isochoric differential x-ray experiments of Bosio, Chen, and Teixeira are consistent with the possibility that water molecules can exist in distinct configurations characterized by either four or five neighbors in the first coordination shell. Associated with the molecules with five neighbors are defects in the tetrahedral bond network ("bifurcated bonds") which offer paths with low energy barriers between different network configurations and in turn enable the fast restructuring of the network with thermal energies k(T) much smaller than the hydrogen-bond energy.