Nearest neighbor bond, weakening

The water-water distance at the nearest neighbor, r, increased and the number of water molecules at the nearest neighbor, j, decreased with the increase in temperature and pressure. The results indicated that the hydrogen bonds between water molecules were elongated and the hydrogen-bonded water structure was going to be decomposed at elevated temperature and pressure. The cr value also increases with t and p, and the result showed that the water-water interaction was weakened when t and p were elevated. 

Figure 3.54. Schematic illustration of the use of Bond Order Conservation to predict attractive or repulsive interaction between adsorbates, (a) Adsorbates which bond to the same surface metal atom are weakened by the presence of one another as the result of competition for electron density from the same metal atom. These interactions are repulsive, (b) Adsorbates that are bound to metal atoms which are neighbors have an effective attractive interaction, because of the weakening of the metal—metal bond due to their coadsorption. Bond order conservation indicates that attractive and repulsive interactions alternate through bonds. Binding to a next-nearest metal atom neighbor such as K" versus A has a weaker interaction and, hence, this through-surface interaction is repulsive.

---