Larger Water Clusters

these studies have been extended to clusters as large as 20 water monomers (see Laasonen and Klein, 1994). 

---

Five calculated OH-stretching vibrations of the PhOH-W2-l structure are presented in Table 35. By analogy with the PhOH-wi-l complex, the hydrogen-bonded phenolic vqh vibration is red-shifted significantly by 202 cm and its IR intensity is enhanced by a factor of 4.9 while its Raman activity only doubles. The other four vibrations are simply assigned to the vj and V3 of water molecules Wadi and Wadi, although their collective nature (essential for larger water clusters) should be noted. One pair of them, v and... 

The chemical shift of the water molecules adsorbed on MS is bg 3 ppm but for the MIX sample, it is characterized by two signals 5e=1 and 4 ppm. The first one can be attributed to single water molecules localized under cross-linked DMS umbrella. This Sg value is lower than those for nonassociated water molecules in inert chloroform or benzene because the DMS groups are very hydrophobic (the siloxane bonds Si-O-Si are rather hydrophobic too) and create the barriers for the formation of larger water clusters in contact with residual silanols on MS. More intensive signal at h=4 ppm is due to SAW forming large clusters and nanodomains. 

PFSA PEMs at various hydration levels and lECs. They found that longer sidechains lead to the formation of larger aggregates of sulfonate groups and consequently to larger water clusters, with cluster sizes varying from 2 to 13 nm for 5 < A, < 16. 

---