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Szeged Index
In chemical graph theory, the Szeged index is a topological index of a molecule, used in biochemistry. The Szeged index, introduced by Iván Gutman, generalizes the concept of the Wiener index introduced by Harry Wiener. The Szeged index of a connected graph ''G'' is defined as : Sz(G)=\sum_ n_1(e\mid G)n_2(e\mid G), If ''e'' is an edge of ''G'' connecting vertices ''u'' and ''v'', then we write ''e'' = ''uv'' or ''e'' = ''vu''. For e=uv\in E(G), let n_1(e\mid G) and n_2(e\mid G) be respectively the number of vertices of ''G'' lying closer to vertex ''u'' than to vertex ''v'' and the number of vertices of ''G'' lying closer to vertex ''v'' than to vertex ''u''. Szeged index plays an important role in information theory. One way to measure a network structure is through the so-called topological indices. Szeged index has been shown to correlate well with numerous biological Biology is the scientific study of life. It is a natural science with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Graph Theory
Chemical graph theory is the topology branch of mathematical chemistry which applies graph theory to mathematical modelling of chemical phenomena. The pioneers of chemical graph theory are Alexandru Balaban, Ante Graovac, Iván Gutman, Haruo Hosoya, Milan Randić and Nenad Trinajstić (also Harry Wiener and others). In 1988, it was reported that several hundred researchers worked in this area, producing about 500 articles annually. A number of monographs have been written in the area, including the two-volume comprehensive text by Trinajstić, ''Chemical Graph Theory'', that summarized the field up to mid-1980s. The adherents of the theory maintain that the properties of a chemical graph (i.e., a graph-theoretical representation of a molecule) give valuable insights into the chemical phenomena. Others contend that graphs play only a fringe role in chemical research.D.H. Rouvray, "Combinatorics in Chemistry", pp. 1955-1982, in: Ronald Graham, Martin Grötschel, László Lová ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
