Hydroxy-terminated self-assembled monolayers

The advancing contact angles of 110 -112° for the methyl-terminated self-assembled monolayer and of 55° for the hydroxy-terminated surfaces support the model of an organized layer with the -CH3 and -OH end groups of the amphiphilic molecules being exposed to the ambient environment (vacuum, air, or water) and with the phosphate groups being oriented toward the substrate. 

The molecular ion (M — H) intensity of the methyl-terminated phosphate is 1 order of magnitude greater than that of the hydroxy-terminated phosphate. It has been reported that the detection of molecular mass ions M - H is correlated with the degree of order in self-assembled monolayers, resulting from energy transfer and stability effects. We assume that the higher count rate... 

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