Metallic Bonding: Definition
- Metal atoms are tightly packed together in lattice structures
- When the metal atoms are in lattice structures, the electrons in their outer shells are free to move through the structure
- The free-moving electrons are called ‘delocalised electrons’ and they are not bound to their atom
- When the electrons are delocalised, the metal atoms become positively charged
- The positive charges repel each other and keep the neatly arranged lattice in place
- There are very strong electrostatic forces between the positive metal centres and the ‘sea’ of delocalised electrons
- The strength of electrostatic attraction can be increased by:
- Increasing the number of delocalised electrons per metal atom
- Increasing the positive charges on the metal centres in the lattice
- Decreasing the size of the metal ions
- Due to the delocalised ‘sea’ of electrons, metallic structures have some characteristic properties