Inelastic tunneling spectroscopy

Troisi A, Beebe JM, Picraux LB, Zee RDv, Stewart DR, Ratner MA, Kushmerick JG (2007) Tracing electronic pathways in molecules by using inelastic tunneling spectroscopy. Proc Natl Acad Sci USA 104(36)44255-14259... 

In the context of this chapter, STM data of (co-)adsorbed molecules under UHV and at elevated pressures provide complementary information. When available, such investigations were included here and are briefly discussed. Applications of STM in related fields are numerous one fascinating example is single-molecule spectroscopy by inelastic tunneling spectroscopy (lETS) (223-225). 

Modem enhancement techniques enable the signal-to-noise ratio to be increased by interactions with surface plasmons (33) or surface effects (34). Inelastic tunneling spectroscopy (35), Brillouin scattering (36), and photoacoustic spectroscopy (37) have also been used to explore the vibrational modes in LB films. 

A MINDO/3 method has been used to calculate the electronic structure of polyethylene,127 and comparison has been made with the photoelectron spectrum. Extended Huckel calculations on six fluorinated compounds derived from linear polyethylene have been carried out with the same objective.128 The circular dichroism of unordered polymers has been treated on the basis of time-dependent Hartree theory,129 130 131 and high-resolution inelastic tunnelling spectroscopy of macromolecules has been reported.180... 

The chemical reactions occurring are probably similar to those described above for glass (22). Supporting evidence that amino compounds are chemisorbed by metal oxide surfaces has recently been obtained by inelastic tunnelling spectroscopy (23). Further investigations are being carried out to find explanations for the differences observed in the effects of amine surface treatment of glass and of metal on the adhesion of this polyurethane to the substrate. 

One of the key criticisms levelled at STM for many years was its inability to provide detailed structural information or routinely yield chemical signatures of molecules. This is because the technique provides maps of the local density of states within an energy window defined by the tip-sample bias. These generally do not contain direct structural and/or chemical information which can be easily extracted. Inelastic tunnelling spectroscopy, as pioneered in the STM context by Wilson Ho and co-workers, certainly provides a mechanism for chemical identification but the technique... 

Wang, W., Scott, A., Gergel-Hackett, N. et al. 2008 Probing molecules in integrated silicon-molecule-metal junctions by inelastic tunneling spectroscopy. Nano Lett. 8 478 84. 

Inelastic tunneling spectroscopy (lETS) [55] is arelated local spectroscopic technique that allows the identification of an adsorbed molecule by the excitation and... 

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