Structural Mathematical Models Describing Water Clusters

Abstract

In this review it is reported about the research on the structure of intermolecular water cyclic associates (clusters) with general formula (Н2О)n and their charged ionic clusters [(Н2О)n] + and [(Н2О)n]-by means of computer modeling and spectroscopy methods as 1 Н-NMR, IR-spectroscopy, DNES, EXAFS-spectroscopy, X-Ray and neurons diffraction. The computer calculation of polyhedral nanoclusters (Н2О)n, where n = 3-20 are carried out. Based on this data the main structural mathematical models describing water structure (quasicrystalline, continious, fractal, fractal-clathrate) have been examined and some important physical characteristics were obtained. The average energy of hydrogen bonding (EH…O) between Н2О molecules in the process of cluster formation was measured by the DNES method compiles-0,1067±0,0011 eV. It was also shown that water clusters formed from D2О were more stable, than those ones from Н2О due to isotopic effects of deuterium.

Explanation for the Mpemba Effect

“…The hydrogen bond energy is 5 -10 kcal/mole, while the energy of О-Н covalent bond in the Н 2 О molecule is 109 kcal/mole. The average energy (ΔE H…O) of the hydrogen Н…О bonds between Н 2 О molecules is 0.1067 ± 0.0011 eV [14].…”

“…Cold water has a rudimentary structure, hereinafter referred to as simply the "structure". The structure consists of intermolecular cyclic associates (clusters) of water with the general formula (Н 2 О)n [14]. The ordering of water molecules into associates corresponds to a decrease in their entropy (randomness) [14].…”

“…The structure consists of intermolecular cyclic associates (clusters) of water with the general formula (Н 2 О)n [14]. The ordering of water molecules into associates corresponds to a decrease in their entropy (randomness) [14]. Each water molecule can form two hydrogen bonds involving their hydrogen atoms plus two further hydrogen bonds utilizing the hydrogen atoms attached to neighboring water molecules.…”

“…The average energy of the hydrogen bonds between the Н 2 О molecules during the process of cluster formation is 0.1067 ± 0.0011 eV. As the energy of the hydrogen bonds between the Н 2 О molecules increases to 0.14 eV, the water clusters are destroyed [14]. A typical cluster consists of five water molecules.…”

“…With fluctuations in the temperature of water, the average energy of the hydrogen H…O bonds in the water molecule clusters changes [14]. This is the reason that the hydrogen bonds in the liquid state are relatively weak and unstable: it is thought that they form and break readily with changes in the temperature.…”