By the covalent bond will be non-metals. They have a tendency to additional electrons. In order to fully occupy Elektronenoktett, share the binding partners or more electron pairs. The electrons then surrounded both binding partners and allow them a more favorable energetic state. The repelling effect between atomic nuclei are ultimately prevails, the resulting attraction, the resulting joint electron shell conveys.



Figure 4: Covalent binding (=binding atomic)

In the last two ties are described in a pure crystal untied no charge for disposal over the entire solid can be moved.