Flat-lying

Au surfaces yielded analogous results. Here the authors foimd gauche defects only in the second layer, while the first represented a flat lying chain [133]. 

Micromechanics theories for closed cell foams are less well advanced for than those for open cell foams. The elastic moduli of the closed-cell Kelvin foam were obtained by Finite Element Analysis (FEA) by Kraynik and co-workers (a. 14), and the high strain compressive response predicted by Mills and Zhu (a. 15). The Young s moduli predicted by the Kraynik model, which assumes the cell faces remain flat, lie above the experimental data (Figure 7), while those predicted by the Mills and Zhu model, which assumes that inplane compressive stresses will buckle faces, lie beneath the data. The experimental data is closer to the Mills and Zhu model at low densities, but closer to the Kraynik theory at high foam densities. 

Potential-induced phase transition of trimesic acid on Au(lll) electrode has been studied using in situ STM and CV [325]. In cyclic voltammograms, a pair of peaks was formed, which was ascribed to the structural transformation. On the basis of high-resolution STM images in 0.1 M HCIO4, it has been proposed that trimesic acid molecules assume flat-lying and vertical orientations at 0.25 V and 0.85 V, respectively. Both orientations coexisted at 0.65 V. 

The Hungarian and Russian schools seem to prefer cyclization with five carbon atoms flatly lying on the surface (see, for review, 201). This is only possible when no more than one c-bond per carbon atom is formed toward the underlying metal atoms, since multiple bonds would probably lift the molecule away from the surface. However, the a-bonds are usually well localized (of course, one does not know for certain when metals are involved... 

Cyclooctatetraene and the 1,5- and 1,3-cyclooctadienes on Pt(lll) also gave a common product at higher temperatures, which, from the simplicity of the spectrum, is postulated to be flat-lying C8H8. This possibly involves 77-electron donation to the surface in order to overcome antiaromaticity. 

Gao et al. (346) obtained SER spectra of toluene, isopropylbenzene, and ferf-butylbcnzene on roughened gold electrodes. The spectra are reasonably interpreted in terms of flat-lying molecules, 77-bonded to the surface via the aromatic ring. However, one imagines that the 77-bonding must be weaker in the presence of the bulky ferf-butyl substituent, and for this molecule all the bands in the spectrum of the liquid occur also in the SER spectrum. (The normal Raman spectrum shown in Fig. 2A of the Gao et al. paper (346) is that of isopropylbenzene rather than that of the indicated toluene.)... 

Figure 2. The increase of rank of coal (vitrite) with depth, based on data from deep borings with flat lying beds (scheme according to Patteisky and M. Teichmiiller (17))...

The RAIRS spectra for NO on Mo2C display peaks at 1800 and 1761 cm-1. These peaks are characteristic of on-top bonded NO.39 Terminally bonded NO on Ru(001) displays a stretching frequency of about 1790-1820 cm-1. By analogy with the discussion of the CO TPD and RAIRS data, we attribute the peaks at 1800 and 1761 cm-1 to on-top adsorption on two distinct Mo sites. Again, it must be noted that the RAIRS results cannot be used to rule out the presence of tilted or flat-lying states on the Mo2C surface. Indeed, Hayden et al,36 only detected the on-top NO species in a RAIRS study of NO on Ru(001) despite the fact that NO adsorbed in the hollow site exhibits a dipole scattering mode in EELS measurements. 

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