Taylor-Howison hypothesis

For a CaO/Si02 ratio of 1.5, the pseudocell of the modified Taylor-Howison hypothesis contains 3.30 molecules of CaO, 2.20 molecules of Si02, and 2.20 molecules of H20. Thus, the cell is 10% heavier than the one in the model discussed before, which results in a 10% smaller specific surface area. The specific surface area for the two-layer tobermorite is 343 sq. meters per gram for the three-layer tobermorite, 229 sq. meters per grams. The corresponding CaO/Si02 ratios, from... 

In the model described earlier, the addition of two molecules of lime results in the disappearance of a unit surface. A similar calculation, based on the modified Taylor-Howison hypothesis, leads to the conclusion that the substitution of 0.78 molecule of CaO for Si02 causes the disappearance of a unit surface. This substitution is equivalent to the replacement by CaO of one molecule of Si02 out of 8.58 molecules. 

The Taylor-Howison hypothesis gives an almost identical structure for the three-layer tobermorite with the one shown in Figure 8 the pseudocell surface contains one molecule of Si02 and 0.75 molecule of CaO, and the CaO content of the layers between the pseudocells is 1.50 molecules. The two-layer structure, however, shows greater differences. The surface is not very different it contains... 

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