Thallium bilayer

Tl,Bi)-1223 or (Tl,Pb)-1223 are selected for detailed description as representatives of the thallium bilayer and monolayer compound, respectively. Tl-2201 is selected because of its structural simplicity and continuously variable T, up to 84 K. It is the ideal candidate for fundamental studies. (Tl,Bi)-1223 and (Tl,Pb)-1223 offer a high irreversibility of field, which is very important for applications in high magnetic field. 

Waszczuk et al. [329] have carried out radiometric studies of UPD of thallium on single-crystal Ag electrode from perchloric acid solutions. Deposition of Tl on Ag(lOO) to obtain monolayer, bilayer, and bulk crystallites has been studied by Wang et al. [330]. These studies have shown that apart from the substrate geometry, the nature of the substrate-adatom interactions also influence the structure of the UPD metal adlayers. This is because of the fact that, contrary to Au and Pt electrodes, Tl forms a well-ordered bilayer phase before bulk deposition on Ag(lOO) surface occurs. 

A few studies of mammalian cells by XPS were reported in the seventies. This was reviewed by Millard. XPS combined with etching allowed to detect the increase of calcium concentration, especially in the cytoplasm subjacent to the plasma membrane, following activation of the DNA synthesis of hepatoma cells. Similarly, XPS study combined with etching of red blood cells allowed the presence of thallium located at a depth of about lOmn to be revealed. Thallium may be an activator of enzymes located in and below the phospholipids bilayer. Iron was only detected at a depth of about 50 nm. ... 

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