Interaction of dimethyl methylphosphonate with alkanethiolate monolayers studied by temperature-programmed desorption and infrared spectroscopy
1997 (English)In: JOURNAL OF PHYSICAL CHEMISTRY B, ISSN 1089-5647, Vol. 101, no 31, 6021-6027 p.Article in journal (Refereed) Published
The adsorption of dimethyl methylphosphonate (DMMP) on well-defined organic surfaces consisting of self-assembled monolayers (SAMs) of omega-substituted alkanethiolates on gold has been studied. Three different surfaces were examined: one terminated with -OH groups (Au/S-(CH2)(16)-OH), one with -CH3 (Au/S-(CH2)(15)-CH3), and one mixed surface with approximately equal amounts of -OH and -CH3 terminated thiols. Detailed information about the nature and strength of the interaction was gathered by infrared reflection-absorption spectroscopy and temperature-programmed desorption under ultrahigh-vacuum conditions. It is found that the outermost functional groups of the thiol monolayer have a pronounced impact on the interaction with DMMP at low coverage. The -OH surface, allowing for hydrogen bonds with the P=O part of the DMMP molecule, increases the strength of interaction by approximately 3.8 kJ/mol as compared to the -CH3 surface. A preadsorbed layer of D2O leads to stronger interaction on all surfaces. This is explained by additional hydrogen bond formation between free O-D at the ice-vacuum interface and DMMP.
Place, publisher, year, edition, pages
AMER CHEMICAL SOC , 1997. Vol. 101, no 31, 6021-6027 p.
National CategoryEngineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-76335DOI: 10.1021/jp9707605ISI: A1997XP10700015OAI: oai:DiVA.org:liu-76335DiVA: diva2:513891