Structure of diamond
In diamond every atom is bonded with the other by covalent links resulting in the formation of giant molecule. Each carbon atom is linked with four neighbouring carbon atoms held at the corners of a regular tetrahedron by covalent bonds. The C-C bonds are very strong. The crystal of diamond is very hard and has high melting and boiling points.
The combined strength of the many carbon-carbon bonds within the structure of diamond give it both great hardness and a lack of chemical reactivity.
Structure of graphite
It consists of separate layers. The carbon atoms are arranged in regular hexagons in flat parallel layers. There is no strong bonding between different layers, which are, therefore, easily separable from each other. Since there are no covalent linkages between the adjacent planes, graphite can be easily cleaves along the lines of the planes. Whilst the bonds within the layers are strong, those between the layers are not and so they slide over each other easily This accounts for the softness and lubricating power of graphite.
Structure of Buckminster fullerenes
In 1985, a new allotrope of carbon was discovered by Richard Smalley and Robert Curl of Rice University, Texas, working with Harry Kroto of Sussex University. The first to be identified and the most symmetrical of the family, with 60 atoms and 32 sides (20 hexagons and 12 pentagons), was nick named `buckyball' and was then named buck minister fullerene, because it resembles the geodesic domes developed by an American inventor called R.Buckminister fuller. The group of spherical carbon molecules is called fullerenes. These compounds have superconducting properties and its potential for opening new areas of chemistry have made study of the `buckyball' as one of the most rapidly expanding areas of chemical research.
Copyright © 2018-2021 BrainKart.com; All Rights Reserved. (BS) Developed by Therithal info, Chennai.