Mercury-like metals

Although the validity of physical prerequisites, on which is based the photoemission theory that lead to the discovery of the five-halves law, was disputed in nonetheless the existence of this law confirmed experimentally can be considered to be a well-founded fact at least for mercury and mercury-like metal electrodes (used in our experiments)... 

Significant new information was provided by capacitance measurements at single-crystal faces of solid metals. It was found that there existed two groups of solid metals having qualitatively different properties. One of them includes numerous mercury-like metals or semimetals. 

In contrast to mercury-like metals, the adsorption of ions on platinum metals appears to be relatively slow [68], the adsorption rate Vajj exponentially decreasing with the surface coverage 0 in accordance with Roginskii-Zel dovich equation... 

A considerably higher overpotential, close to the values for mercury-like metals, was obtained in [162]. The reason behind such a discrepancy is not yet clear. 

The facts presented above firmly establish the existence of a barrierless discharge of hydrogen ions (as well as a barrierless reduction of undissociated acid molecules or their corresponding ion pairs) at mercury in aqueous and ethylene glycol solutions, and at silver in aqueous solutions. From this point of view, let us consider the available data on the evolution of hydrogen at other cathodes, starting with mercury-like" metals which poorly adsorb hydrogen. 

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