Ligand passivating

Fig. 1. Ligand-field model for the electronic structure of substitutional hydrogen in silicon in terms of the interactions between the vacancy orbitals and the atomic-hydrogen orbitals [Although the a state is shown as being not entirely passivated (still below the bottom of the conduction-band edge), it could in fact be in the conduction band, but with a host-like state pushed down slightly into the band gap.] (Reprinted with permission from the American Physical Society, DeLeo, G.G., Fowler, W.B., Watkins, G.D. (1984). Phys. Rev. B 29, 1819.)...

Mercury can influence ion, water, and nonelectrolyte transport in different cells [ 14, 77]. The cell membrane is believed to be the first point of attack by heavy metals however, intracellular enzymes and metabolic processes may also be inhibited [70, 78, 79]. The attachment of heavy metals to ligands in or on the plasma membrane may result in changes in passive permeability or selective blockage of specific transport processes. Many membrane transport systems are known to be sensitive to sulphydryl-group modification [ 14, 80, 81]. 

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