Distance tunneling spectra

Fig. 5. A) Voltage tunneling spectra on 5/15/40 run oxide covered Sputter-titanium recorded with Au-tip, vmder dry nitrogen atmosphere. B) Distance tunneling spectrum on an 5 nm oxide covered titanium, under dry nitrogen (I) and wet air (II), scan rate 3 nm/s, bias -IV.

Deng W, Hipps KW (2003) Tip-sample distance dependence in the STM-based orbital-mediated tunneling spectrum of nickel(II) tetraphenylporphyrin deposited on Au(lll). J Phys Chem B 107 10736-10740... 

Fig. 14.3. Dependence of local tunneling spectra with distance. By moving a tip with atomic resolution closer and closer to the sample surface, the features in the tunneling spectra is broadened. At the contact point, the tunneling spectrum becomes featureless. This phenomenon demonstrates the effect of local modification of the sample wavefunction and the consequence of uncertainty principle in scanning tunneling spectroscopy. (After Avouris et al., 1991b.)...

The tetramer is also cyclic ", as illustrated in Fig. 5.24, and with a greater degree of symmetry than the trimer, belonging to the point group. The ring is sequential in the sense that each molecule acts as simultaneous donor and acceptor. This type of structure has been confirmed by analysis of the far-IR vibration-rotation tunneling spectrum . The correlated R(O- O) distances are all equal to 2.743 A, about 0.06 A shorter than in the trimer. (The ex-... 

Pettinger et al. observed a TERS spectrum of monolayer-thick brilliant cresyl blue (BCB) adsorbed on a smooth Au film surface by using a Ag tip, while no STM image of the adsorbed surface was shovm [23]. The Raman intensity increased when the tip was in the tunneling position, meaning that the tip-surface distance was around 1 nm. They calculated the field enhancement factor by the method described by... 

A simulation has been carried out [105, 106, 119] of the process of accumulation of the immobile Frenkel defects restricted by tunnelling recombination of dissimilar defects, as it is observed in many solid insulators. As follows from Chapter 3, in contrast to the ionic process of instant annihilation of close pairs of the vacancy-atom type, it is characterized by a broad spectrum of recombination times. Thus, the probability for a pair of chosen defects that lie at the relative distance r to survive for r seconds is... 

The method proposed in ref. 71 for estimating the distance of tunneling is based on taking account of the effect produced by the magnetic dipole-dipole interactions of two paramagnetic reagents [the total electron spin of such a radical pair (RP) S = 1] on the shape of their EPR spectrum. The shape of the EPR line in the case of a constant distance, R, between reagents can be calculated from the formula... 

Willig and co-workers used near-infrared spectroscopy to measure excited-state interfacial electron transfer rates after pulsed light excitation of cis-Ru(dcb)2(NCS)2-Ti02 in vacuum from 20 to 295 K [208]. They reported that excited-state electron injection occurred in less than 25 fs, prior to the redistribution of the excited-state vibrational energy, and that the classical Gerischer model for electron injection was inappropriate for this process. They concluded that the injection reaction is controlled by the electronic tunneling barrier and by the escape of the initially prepared wave packet describing the hot electron from the reaction distance of the oxidized dye molecule. It appears that some sensitizer decomposition occurred in these studies as the transient spectrum was reported to be similar to that of the thermal oxidation product of m-Ru(dcb)2(NCS)2. 

Fig. 10.20 Comparison of an RRS spectrum with the tip-enhanced Raman spectrum for brilliant cresyl blue on a smooth gold film. Coverage 0.5 M. Tunneling distance 1 nm, retracted distance 1000 nm. Laser power at the sample ca. 5 mW at A=633 nm. (Reprinted with permission from Ref. [87].)...

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