Molecular crystal

A molecular crystal is a crystal with a recognizable molecules that are held together by weak physical bonding such as van der Waals forces or hydrogen bonding as opposed to chemical bonding like covalent or metallic bonds.

In such a type of crystal, the constituent particles are molecules. They are formed due to covalent bonds between the atoms. If the centre of negative charges and the centre of positive charges coincide in a molecule, such a molecule is called a non polar molecule. The bond between polar molecules is called a dipole-dipole bond whereas the bond between non-polar molecules is called Van-der-waal's bond. Molecular solids are usually soft, have low melting points and are poor conductors of electricity.

Examples include ice, iodine, solid carbon dioxide (dry ice) and rock candy (sucrose).