In molecular solids, the constituents are neutral molecules. They are held together by weak vander Waals forces. Generally molecular solids are soft and they do not conduct electricity. These molecular solids are further classified into three types.
1. Non polar molecular solids.
2. Polar molecular solids.
3. Hydrogen bonded molecular solids.
1. Non polar molecular solids
- In this type, molecules are held together by weak dispersion forces or London forces.
- They have low melting points and are usually in liquids or gaseous state at room temperature.
Examples – Naphthalene, Anthracene etc.
2. Polar molecular solids
- In this type, molecules formed by polar covalent bonds.
- They are held together by strong dipole-dipole interactions.
- They have higher melting points than the non – polar molecular solids.
Examples., solid CO2 , solid NH3
3. Hydrogen bonded molecular solids
- The constituents are held together by hydrogen bonds.
- The constituents are held together by hydrogen bonds.
- They are soft solids under room temperature
Examples: Solid ice, glucose, urea.
