Atomic Level Studies

Studies of the first atomic layer in the formation of a compound are essentially studies of UPD. As noted, there are a number of excellent reviews [83-85, 87, 88], To really learn about the structure of UPD layers, single crystals and surface sensitive analytical techniques are required. A recent review covers atomic level studies of UPD on important single crystal electrode interfaces, such as Au, Pt, Ag and Cu [88], but does not go deeply into most of the systems of interest for EC-ALE. In this section, UPD of the first atomic layers in the formation of a compound will be discussed, as will atomic level studies of the formation of the first monolayers of compounds, where information is available. 

Studies of UPD are important for a number of reasons, most importantly, because they are the formation of the first atomic layer in an electrodeposit. In the present text, they are important because they illuminate the structures of electro-deposited atomic layers, the reactants in EC-ALE. However, such studies must be kept in context, given that the structures of the first UPD layers on a substrate generally have little to do with the structures of subsequently formed compound mono-layers. It has been found that the structures of compound monolayers are determined, for the most part, by the structure of the compound that is forming, perturbed by the lattice mismatch between the deposit and the substrate. The structure of the first atomic layer on the substrate does not appear to be a significant factor in determining 

The technology for making single crystal ball electrodes is inexpensive and well developed [223, 224], Wire of the noble metals Au and Pt can be melted in a hydrogen oxygen flame. By careful manipulation of the flame on the ball, it can be recrystallized repeatedly to form a perfect single crystal. The crystals have a set of flat spots, [111] planes, which develop on the surface. These facets feature some of the 

---

Atomic level studies of complex peptide and protein energy landscapes have become more detailed as computers have become faster, allowing for longer sampling simulations... 

Lister TE, Stickney JL (1996) Atomic level studies of selenium electrodeposition on gold(lll) and gold(llO). J Phys Chem 100 19568-19576... 

The first atomic level study of an EC-ALE system was of Te [235] and Cd atomic layers on Au single crystal surfaces [156, 157], using UHV-EC techniques [131] and some ex-situ STM. Those experiments involved emersion (removal) of the crystals from solution and transfer to UHV for analysis (Figure 42). 

Some atomic level studies of CdSe formation have been performed, using STM, AES and LEED [161, 162]. The structures formed by reduction of HScO, on the low index planes of Au are described in a number of papers [237, 238, 240, 241], in Section 7.2.3, and are listed in Table 2, for the low index planes of Au. 

Atomic level studies of the first monolayer of CdS on Au(lll) have been published by Shannon et al. [165]. STM was used to study the first atomic layer of S and the... 

Bassolino-Klimas, D., Alper, H. E. and Stouch, T. R. (1993). Solute diffusion in lipid bilayer membranes an atomic level study by molecular dynamics simulation,... 

In addition to studies using photo-resist-covered substrates and AFM, atomic level studies were performed to help identify the nature of the surface-limited reactions used to form the electrochemical digital etching cycle [313]. In those studies the dependence of etched amounts on the potential used for Cd oxidation was investigated using a UHV-FC instrument (Fig. 39). 

D. Bassolino-Klimas, H. E. Alper and T. R. Stouch, Solute Diffusion in Lipid Bilayer Membranes An Atomic Level Study by Molecular Dynamics Simulation, Biochemistry 32 (1993) 12624. 

Previously, the sodium dodecyl sulfate (SDS) surfactant system was also investigated with a 200 ps molecular dynamics computer simulation in the NVT-ensemble (7). In this computer simulation, the parameters of the atomic interaction potential functions were taken from the CHARMM force field. The calculations showed that the SDS micelle remains spherical with a radius of gyration in good agreement with the experimental results. Remarkable motions of the head-groups were observed and the trans to gauche populations are equivalent for the micelle and the analogous hydrocarbon, liquid dodecane. Recently, atomic-level studies of AOT reverse micelles and molecular dynamics simulations of the structure and dynamics of a dode-cylphosphocholine micelle in aqueous solution have been published (8, 9). 

Electrochemical Digital Etching Atomic Level Studies of CdTe(lOO)... 

Atomic layer epitaxy, 117 Atomic level studies of CdTe(lOO), electrochemical digital etching, 115-123 Auger electron spectrometers, 106 Auger electron spectroscopy bisulfate anion adsorption on Au(l 11), Pt(l 11), and Rh(l 11) surfaces, 126-138 to monitor composition of acidified water surfaces, 106-114 underpotential deposition of lead on Cu(lOO) and Cu(lll), 142-154 use for bisulfate anion adsorption, 127... 

In the meantime this situation has changed markedly by the advent of new surface physical methods which enabled atomic level studies with well-defined... 

---