1. Glass: types and analysis

1.1 Non-crystalline solids

• Depending on temperature and pressure, chemical compounds are found in various states of matter. The three most common states are gas, liquid and crystal. The gaseous state is characterized by the fact that the molecules are distant from each other. Their motion is random and disordered. The gaseous state is a non-condensed, disordered state. In the liquid state, molecules are much closer together. The atomic arrangement is disordered at long range, but can exhibit order at short range, i.e. at first neighbors. This condensed state has the ability to flow. The crystal corresponds to an ordered arrangement of atoms following a sequence that translates into a type of structure. This condensed, ordered state has the properties of a solid....