In chemistry, the Natta projection (named for Italian chemist

Giulio Natta Giulio Natta (26 February 1903 – 2 May 1979) was an Italian chemical engineer and Nobel laureate. He won a Nobel Prize in Chemistry in 1963 with Karl Ziegler for work on high polymers. He also received a Lomonosov Gold Medal in 1969. Biograph ...

) is a way to depict

molecules A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioc ...

with complete

stereochemistry Stereochemistry, a subdiscipline of chemistry, involves the study of the relative spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereo ...

in two dimensions in a

skeletal formula The skeletal formula, or line-angle formula or shorthand formula, of an organic compound is a type of molecular structural formula that serves as a shorthand representation of a molecule's bonding and some details of its molecular geometry. A ...

. In a

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

molecule with all carbon atoms making up the backbone in a

tetrahedral molecular geometry In a tetrahedral molecular geometry, a central atom is located at the center with four substituents that are located at the corners of a tetrahedron. The bond angles are cos−1(−) = 109.4712206...° ≈ 109.5° when all four substituents are ...

, the zigzag backbone is in the paper plane (

chemical bond A chemical bond is a lasting attraction between atoms or ions that enables the formation of molecules and crystals. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds, or through the sharing o ...

s depicted as solid

line segment In geometry, a line segment is a part of a straight line that is bounded by two distinct end points, and contains every point on the line that is between its endpoints. The length of a line segment is given by the Euclidean distance between ...

s) with the

substituent A substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. (In organic chemistry and biochemistry, the terms ''substituent'' and '' functional group'', as well as '' ...

s either sticking out of the paper toward the viewer (chemical bonds depicted as solid wedges) or away from the viewer (chemical bonds depicted as dashed wedges). The Natta projection is useful for representing the

tacticity Tacticity (from el, τακτικός, taktikos, "relating to arrangement or order") is the relative stereochemistry of adjacent chiral centers within a macromolecule. The practical significance of tacticity rests on the effects on the physical p ...

of a polymer. Isotacticpolymer

References

* {{cite book , title=Polymer Synthesis: Theory and Practice: Fundamentals, Methods, Experiments , url=https://archive.org/details/polymersynthesis00brau_863 , url-access=limited , author1=Dietrich Braun , author2=Harald Cherdron , author3=Matthias Rehahn , author4=H. Ritter , author5=B. Voit , publisher=Springer , year=2005 , isbn=3-540-20770-8 , pag
10
} Stereochemistry

See also

References