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Fig. 1. The phosphotungstate anion, an example of a polyoxometalate Fig. 2. Aromatic cations (blue) are added to small POM crystals (red) dispersed in water and the subsequent formation of nanotubes. Fig. 3. Fluorescence image, demonstrating that the fluid has travelled into the tube network. Fig.4. Lindqvist structure, W6O19n-( the Lindqvist ion is an iso-polyoxometalate, the other three are hetero-polyoxometalates.)

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          In chemistry, a polyoxometalate (abbreviated POM) is a polyatomic ion, usually an anion, that consists of three or more transition metal oxyanions linked together by shared oxygen atoms to form a large, closed 3-dimensional framework. Examples include vanadium(V), niobium(V), tantalum (V), molybdenum(VI), and tungsten(VI).
      The framework of transition metal oxyanions may enclose one or more hetero atoms such as phosphorus or silicon, themselves sharing neighbouring oxygen atoms with the framework. For example, the phosphotungstate anion [PW₁₂O₄₀]^3- consists of a framework of twelve octahedral tungsten oxyanions surrounding a central phosphate group (fig. 1).
      The team from the University of Glasgow have much experience in developing the chemistry of so-called POMs, and selected salts of the exotic anions [W72Mn12O268X7]40- (X = Si or Ge) as the starting point for their experiments. These large anions have diameters of  just over 1 nm and form insoluble salts with a variety of organic cations. When organic cations C4H10NO added to the aqueous solution containing dispersed solid salt [W72Mn12O268X7] 40, the first step is the formation of a semipermeable membrane around the crystallites (fig. 2).
       The membrane don't prevents the passage of water, but not by organic cations, which leads eventually to the formation of a saturated solution of the component in the POMs 'sack'. The high osmotic pressure, due to the constant flow of water is constantly increasing, until, finally, the internal pressure does not lead to the conditions under which the membrane to burst. When this happens, is strictly a saturated solution of POM shoots in the solution and on the boundary of two media the formation of new wall membrane in the form of a tube. The flow of saturated solution comes continuously along the tube, which leads to continuous growth at the end.  This process continues until the internal supply of POM will be exhausted, which leads to the formation of hollow tubes for a few micro-or millimeter scale. The composition of nanotubes is determined by the following sequence of elements -- [(C4H10NO)40[W72M12O268X7]] where (X = Si, or X = Ge).
       Extraordinary control over the topology, topography and diameter of the nanotube are obvious advantages of such a structure. It is also worth noting the homogeneity of the material, which is inherent in these entities. The direction of growth can be in control as the change of external polarization (applying a voltage across the solution between two electrodes in solution [system with acceleration voltages of 10–20 kV]), so and mechanical, puncturing the tube deliberately at specific points can be used to design branched tube networks. Nanotubes also are strong enough in order to receive the liquid from the outside, without a break or leak. This was proven by entering fluorescent dyes through the needle micromanipulator (fig.3).
       Will researched the semiconducting properties of this material, because the attended reaction to an external, very small, the potential and has already expressed many assumptions about the introduction of nanotubes in information technology, such as storage information on the nanoscale. Also in this direction are considered some structures containing transition metal atoms with unpaired electrons, who have unusual magnetic properties.
By some estimates the chemical nature of the material suggests the emergence of a number of new technologies. For example, in the fight against cancer, such technology could be useful at the level of direct exposure to the cell, so-called target cell clusters. Super-small size of framework, even suggested the construction of necessary biologically active structures directly in the cells.
       These studies provide ability to develop microfluidic systems, which, among other things, allow controlling the catalytic function of the material at the nano-level. Also this makes them useful as catalysts for various organic reactions. The task of this level is particularly important now, because modern technology descend closer and closer to the level of nano.
       Reproducibility, scalability, synthesis, ease of assembly and manufacture of nanotubes as well, will undoubtedly play a significant role in setting priorities between the materials of the future.
The inclusion of organic components, in this case, cations, raises almost infinite variety of classes of materials that may be presented to solve the widest range of tasks by the simple combination of cationic and anionic materials react to form insoluble (unresolved) species.
       For example a discrete polyoxometalate Lindqvist ion (fig.4.) of the form W₆O₁₉^2- was successfully imaged recently for the first time within the capillary of a carbon nanotube following steric locking of the anion with the tubule. In situ relaxation of the anion in its equatorial plane was demonstrated.
       Some potential "green" applications have been reported, such as a non-chlorine  based, wood pulp bleaching process and a method of decontaminating water.
       POM nucleus represent the world new opportunities in applications, which will be based on the unusual magnetic and optical properties. Developed the potential medical applications, the problem is related to antitumor and antiviral effects.
       Connection nanoparticles, interfacial self-assembly of polymers and amphiphilic systems, or combinations of these will, as some claim, to understand even such aspects as the emergence and formation of life in general.