Hydrogen Bonds on Surfaces

Herwig, K.W. and Trouw, F.R. (1992). Ethanol on graphite the influence of hydrogen bonding on surface melting. Phys. Rev. Lett., 69, 89-92. 

Because the cis-decalin molecule extends its two methine carbon-hydrogen bonds on the same side in contrast to frans-decalin, the carbon-hydrogen bond dissociation of adsorbed decalin would be advantageous to the cis-isomer on the catalyst surface (Figure 13.17). A possible reaction path by octalin to naphthalene in dehydrogeno-aromatization of decalin will be favored to the cis-isomer, since its alkyl intermediate provides the second hydrogen atom from the methine group to the surface active site easily. 

The interaction on silanated slides is thought to be the result of a combination of electrostatic and hydrogen bonding. Aminosilane surfaces are positively charged at neutral pH. Printing under alkaline conditions shifts... 

Adsorption of pyridine on goethite and on hematite involved both coordination to the Lewis acid sites and hydrogen bonding to surface OH groups. Trimethylchlorosil-ane reacted with the surface OH groups on these oxides to form surface trimethyl siloxyl groups and HCI (Rochester and Topham, 1979c). 

Coadsorption of ammonia and hydrogen fluoride with water on Ag(llO) has been described by Krasnopoler et al. [127] as an example of hydrogen bonding and surface... 

The electron rich amine function is a good acceptor for hydrogen bonds. On the other hand, the basic character of the amine causes proton transfer from acidic groups. Both types of interaction occur on the silica surface. Together with the siloxane bond formation, three types of hydroxyl-specific interaction of the aminosilane molecule with the silica surface may be described, for the modification in organic solvent. These are displayed in figure 9.23. 

Phosphoryl chloride, 0=PC13, does not chemically adsorb on silica at room temperature, but it strongly hydrogen bonds with surface silanol groups. 

Phosphorescence measurements of benzophenone adsorbed on Ti/Al binary oxides show the presence of its protonated form in addition to benzophenone hydrogen-bonded to surface OH groups (Nishiguchi... 

Since riboflavin (RF) is surface-active and possesses a high fluorescence quantum yield, the dye is very suitable for TIR fluorescence measurements at a water/oil interface. For TIR experiments, an aqueous RF solution was poured onto a CCI4 solution containing a diamino-j-triazine derivative (DTT), which acted as a flavin receptor via triple hydrogen bonds. On the basis of fluorescence dynamic measurements of RF adsorbed on a water/oil... 

We have reviewed theoretical approaches concerning perfect surface. Defects modify the adsorption. Hydration can strongly perturb the conclusions. If water saturates the adsorption sites, the admolecule should either displace an adsorbed molecule (and has to be more strongly adsorbed than water itself) or adsorb by hydrogen bonding on an ice layer. Such layers are formed on MgO(lOO) surfaces[3, 24, 80]. 

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