Amorphous State

  • Stepan S. Batsanov
  • Andrei S. Batsanov


Below certain grain size, estimated from X-ray diffraction or thermodynamic calculations as 1 to 5 nm, a crystal loses its long-range order due to increased fraction of surface atoms with incomplete and distorted coordination. If a sharp freezing or a chemical reaction under shock compression precludes the growth of bigger particles, an amorphous solid (glass) will result. The structural chemistry of melting is discussed in terms of average bond distances and effective coordination numbers. For binary compounds and metals, these usually decrease on melting, but for low-coordinate non-metals tend to increase. The structural science of liquid water and aqueous solutions is briefly reviewed, from the Bernal–Fowler model (1933) to the recent computer simulations and extreme-conditions experiments on dynamic ionization. In diluted solutions of salts, ions replace water molecules and are 4-coordinate, while in concentrated solutions ions coordinate water molecules around them in structures similar to solid hydrates.


Coordination Number Shock Compression Crystalline Hydrate Solvation Sphere Pure Ammonia 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© Springer Science+Business Media Dordrecht 2012

Authors and Affiliations

  1. 1.Institute of Structural Macrokinetics and Materials ScienceRussian Academy of SciencesChernogolovkaRussia
  2. 2.Chemistry DepartmentDurham UniversityDurhamUK

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