Inelastic electron tunneling spectroscopy , chemically

Another technique that has proved useful in establishing chemical bonding of coupling agents at interfaces is inelastic electron tunneling spectroscopy (ITES). For example. Van Velzen [16] examined 3-(trimethoxysilyl)propanethiol by this technique. Approximately monolayer quantities of this silane were adsorbed on the barrier oxide of an aluminum-aluminum oxide-metal tunneling junction two metals were investigated, lead and silver. It was concluded that the silane is... 

Despite the enormous impact that scanning probe methods have had on our understanding of reactions at oxide surfaces, both STM and AFM suffer from the lack of chemical specificity. The application of STM-inelastic electron tunneling spectroscopy is a potential solution as it can be used to measure the vibrational spectrum of individual molecules at the surface [69, 70]. 

As with UV-visible spectroscopy in the bulk, such techniques do not yield chemical identification, so that combining other local spectroscopies with STM is typically necessary to identify the atoms and molecules present. Specialized approaches have been developed for this, such as STM photoemission spectroscopy (PESTM) and inelastic electron tunneling spectroscopy to yield vibrational and other information. This area is extremely promising for further work in combining any number of spectroscopies with the exquisite spatial resolution of STM. 

Inelastic electron tunnelling spectroscopy with the STM allows unambiguous chemical identification of surface species, as demonstrated above. Electronic spectroscopy is also capable of differentiating between limited sets of adsorbates but does not as a rule enable such determinations. The vibrational spectra of isolated molecules also shed light on the chemical environment and bonding changes of minority... 

Many different complementary experimental methods are employed to study tunneling phenomena in chemical systems. Nuclear magnetic resonance (NMR) and electron spin resonance (ESR) studies vibrational spectroscopy by infrared (IR), Raman, and inelastic neutron scattering (INS) ... 

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