Surface potential map

Select benzene from the molecules on screen, and select Surfaces. Potential Map refers to an electrostatic potential map. Select Transparent to present it as a transparent (actually translucent) solid. This will allow you to see the molecular skeleton underneath. The surface is colored red in the n system (indicating negative potential and the fact that this region is attracted to a positive charge), and blue in the a system (indicating positive potential and the fact that this region is repelled by a positive charge). 

Recently, scanning Kelvin probes and microprobes, as high-resolution surface analysis devices, have been developed. They allow one to investigate the lateral distribution of the work functions of the surfaces of various phases, including the determination of the potential profiles of metals and semiconductors under very thin films of electrolytic solution, and also of the surface potential map of various polymer- and biomembranes [50-56], The lateral resolution and the sensitivity are in the 100 nm and ImV ranges, respectively [54],... 

It is common practice to decide reference electrode locations from the results of a surface potential mapping survey. Electrodes are normally embedded at locations with the most negative surface potentials, i.e. the locations most likely to corrode. In new structures, it is common to install reference electrodes at locations most likely to be exposed to future corrosion problems. The number of reference electrodes installed will mainly depend on the size and complexity of the structure and the cost. 

Jacobs, H.O. et al.. Surface potential mapping A qualitative material contrast in SPM,... 

A slight variation of this monolayer picture where the cation is directly located at the surface and the alkyl chain points into the vacuum with the anion located close but offset to the cation has been observed in surface potential mapping studies combined with SFG, and the alkyl chain stiU protruding into the vacuum [29, 32]. However, new X-ray reflectivity studies identified multilayered structures of ionic liquids at the gas-liquid interface in case of cationic species that contain trioctyl ligands. The results point toward preferential anion enrichment at the surface that were not confirmed by spectroscopic results [33] (see Ghapter 1 for more detail and references). 

Another problem which has to be solved in order to achieve the desired integrated view of the global heart is the transfer function from the source potentials of the heart to the body surface potentials which are measured either by routine ECG, vector cardiography, or the new techniques of surface potential mapping (Liebman et al, 1981 Hinsen et al, 1981). The forward problem of transforming known source potentials to surface potential maps, based on electri-... 

Liebman E, Thomas W, Rudy Y, Plonsey R (1981) Electrocardiographic body surface potential maps of the QRS of normal children. J Electrocardiology 14 249-260... 

The major clinical use of ECG analysis, in all its forms, has been restricted to diagnosis alone. The efforts of many researchers, as well as that of industry, has been devoted quite successfully to the interpretation of the morphology of a single beat from a single (or multiple) lead ECG, or of a single frame of a body surface potential map. An impressive effort has also been invested in the analysis... 

The generation of surface ECG or body surface potential maps directly or through transfer coefficients from the epicardium to the body surface (Hersh et al, 1978 Barr et al. 1977 Spach et al., 1975a 1975b 1977). 

Kelvin Force Microscopy (KFM) is closely related to EFM in that it can also provide surface potential maps, but in the form of work-function variations. This is derived by measuring the Contact Potential Difference (CPD) between the surface and the tip. This can be done to a spatial resolution of a couple of nanometers. 

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