Chicken wire (chemistry)

Buckminster­fullerene "Bucky Ball" with a chicken wire-like chemical structure

Chicken wire

The term chicken wire in chemistry is used in different contexts. Most of them relate to the similarity of the regular hexagonal (honeycomb-like) patterns found in certain chemical compounds to the mesh structure commonly seen in real chicken wire.

Polycyclic aromatic hydrocarbons

Polycyclic aromatic hydrocarbons or graphenes—including fullerenes, carbon nanotubes, and graphite—have a hexagonal structure that is often described as chicken wire-like.^[1][2][3]

Hydrogen bonded (dashed) complex between melamine (blue) and cyanuric acid (red)

Hexagonal molecular structures

A hexagonal structure that is often described as chicken wire-like can also be found in other types of chemical compounds. Examples are:

• Non-aromatic polycyclic hydrocarbons, e.g. steroids like cholesterol^[4]
• Flat hexagonal hydrogen bonded trimesic acid (benzene-1,3,5-tricarboxylic acid)^[5] or melamine-cyanuric acid complexes^[6]
• Interwoven molecule chains in the inorganic polymer NaAuS ^[7]
• Complexes of the protein clathrin^[8]

A molecule drawn in "chicken wire notation". This molecule is named tetrahydrocannabinol and is found in Marijuana.

Bond line notation

The skeletal formula is a method to draw structural formulas of organic compounds where lines represent the chemical bonds and the vertices represent implicit carbon atoms.^[9] This notation is sometimes jestingly called chicken wire notation. ^[10][11][12]

Placeholder for organic compounds

Chicken wire is sometimes used as a placeholder name for any organic compound, similar to the use of the name John Doe.^{[citation needed]}

Chemical structure of the fictional molecule 1,2-dimethyl-chickenwire

Chemical joke

It is an old joke in chemistry to draw a polycyclic hexagonal chemical structure and call this fictional compound chickenwire. By adding one or two simple chemical groups to this skeleton, the compound can then be named following the official chemical naming convention. Examples are:

• 1,2-Dimethyl-chickenwire in a cartoon by Nick D. Kim

A "chicken wire surface plot" of an organic molecule

Surface plots

In computational chemistry a chicken wire model or chicken wire surface plot is a way to visualize molecular models by drawing the polygon mesh of their surface (defined e.g. as the van der Waals radius or a certain electron density). ^[13]

References

1. ^ Soccerballs
2. ^ General Chemistry Online: Glossary:
3. ^ Space Chemicals: Scientific American
4. ^ Get Healthy...Get Smart
5. ^ [1]
6. ^ Andrew D. Burrows (2004). "Crystal Engineering Using Multiple Hydrogen Bonds". Structure and Bonding 108: 55–96. doi:10.1007/b14137. ISSN 0081-5993 (Print) ISSN 0081-5993 (Print). http://www.springerlink.com/content/tfb8mwejrw0m7v2r/. 
7. ^ PMID 11670705
8. ^ [2]
9. ^ Template
10. ^ Chem 32 Virtual Manual
11. ^ Stereochemistry and Chirality Part I Problems
12. ^ Chem 32 Virtual Manual
13. ^ MolScript v2.1: Interface to external objects