Fullerenes are an important member of the allotrope of carbon known as fullerenes.

Fullerenes are a class of carbon molecules that are composed of carbon atoms arranged in a unique structure. They are named after the American architect and inventor Buckminster Fuller, who is known for designing structures with a geodesic dome shape that resembles the structure of certain fullerenes.

The two specific fullerenes mentioned in the question, C60 and C70, are some of the most well-known and extensively studied fullerenes. C60, also called buckminsterfullerene or buckyball, is composed of 60 carbon atoms arranged in a soccer ball-like structure with 12 pentagonal and 20 hexagonal faces. C70, on the other hand, has 70 carbon atoms arranged in a similar structure but with additional pentagonal and hexagonal faces.

Fullerenes have unique properties that make them important in various fields of science and technology. Some of these properties include:

1. Molecular Structure: The unique arrangement of carbon atoms in fullerenes gives them a high degree of symmetry and stability.

2. Physical Properties: Fullerenes have high melting and boiling points, as well as high electrical conductivity. They also exhibit interesting optical properties, such as the ability to absorb and emit light in the visible and ultraviolet regions of the electromagnetic spectrum.

3. Chemical Reactivity: Fullerenes can undergo various chemical reactions, making them versatile building blocks for the synthesis of new materials. They can be functionalized by attaching different functional groups to their surface, allowing for the modification of their properties for specific applications.

4. Applications: Fullerenes have found applications in various fields, including medicine, electronics, and materials science. They have been used as drug delivery systems, catalysts, and components of solar cells and electronic devices.

In summary, C60 and C70 are important members of the allotrope of carbon known as fullerenes. These unique carbon molecules have fascinating properties and find applications in a wide range of scientific and technological fields.