Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characteri...Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characterized.Wettability measurement of water on the SAMs demonstrates that molecular packing density in the monolayers increases while the alkyl chain in the molecules is lengthened. Both the n and m values have similar contribution to the wetting property of SAMs. The RA IR spectra reveal that the alkyl chains in the SAMs tilt away dramatically from the surface normal direction with the increase in their length. However, the orientation of azobenzene moiety is found to be influenced slightly by the alkyl chain length, which is due to the tenderness of the molecule.展开更多
The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscop...The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscopy (RA-FTIR). All these azobenzene SAMs have highly-organized and closely-parked structures, with the molecule tilting away gradually from surface normal direction with the increase of end group alkyl length.展开更多
文摘Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characterized.Wettability measurement of water on the SAMs demonstrates that molecular packing density in the monolayers increases while the alkyl chain in the molecules is lengthened. Both the n and m values have similar contribution to the wetting property of SAMs. The RA IR spectra reveal that the alkyl chains in the SAMs tilt away dramatically from the surface normal direction with the increase in their length. However, the orientation of azobenzene moiety is found to be influenced slightly by the alkyl chain length, which is due to the tenderness of the molecule.
文摘The end-group dominated molecular orientation in the azobenzene self-assembled monolayers (SAMs), CnAzoC2SH (n=1-4), on gold was evaluated for the first time by grazing incidence reflection absorption FTIR spectroscopy (RA-FTIR). All these azobenzene SAMs have highly-organized and closely-parked structures, with the molecule tilting away gradually from surface normal direction with the increase of end group alkyl length.
