Topological descriptor

A topological descriptor , often referred to simply as a topological index , is a numerical value derived from the structure of a chemical molecule.

This number is used to correlate chemical properties and biological activity with the molecular structure .

The term topology is used because only a partial aspect of the molecular structure is used to determine the descriptor; in particular, only connectivity is usually considered, i.e. above all which atom is connected to which. Most of all go there

• the number of atoms and
  • related chain lengths and ring sizes measured as atomic number
• the number of neighboring atoms

in the calculation. Only sometimes will be too

• Binding orders
• Distances between atoms
  • related chain lengths and ring sizes as lengths
• Atomic masses and types

included in the calculation.

See also

• Quantitative structure-property relationship
• Wiener index
• Randić index
• Balaban J index

literature

• Qian-Nan Hu, Yi-Zeng Liang, Kai-Tai Fang: The Matrix Expression, Topological Index and Atomic Attribute of Molecular Topological Structure . In: Journal of Data Science . tape 1 , no. 4 , October 2003, p. 391-404 ( jds-online.com [PDF]).
• James Devillers, Alexandru T. Balaban (Editors), Topological Indices and Related Descriptors in QSAR and QSPR , Gordon and Breach (2000)