Indices Zagreb

The two Zagreb indices are applicable to the calculation of -electron energy of conjugated systems 4). 

I. Gutman et al., The graph of atomic orbitals and its basic properties. 2. Zagreb indices. MATCH Commun. Math. Comput. Chem. 53, 225-230 (2005)... 

Wiener index Zagreb indices Randic connectivity index Hosoya Z index... 

Other topological molecular descriptors can be obtained by using suitable functions applied to - local vertex invariants, the most common functions are atom and/or bond additives, resulting in descriptors which give correlation of physico-chemical properties that are atom and/or bond additives themselves. - Zagreb indices and -> ID numbers are derived according to this approach. 

Moreover, several - topological indices are explicitly or implicitly related to the molecular size, such as, for example, - Wiener index, -> Zagreb indices, - Lovasz-Peli-kan index, connectivity indices. 

The most popular molecular descriptors based on the vertex degree are the - connectivity indices, Zagreb indices, - Schultz molecular topological index, and - degree distance of the graph. 

The two Zagreb indices are strictly related to zero-order °x and first-order - connectivity indices, respectively. The 1 Zagreb index M (also called Gutman index) is also related to the - Platt number F and the - connection number Na by the relationship ... 

Walk Counts and Zagreb Indices. Zagreb indices M and M2 have been introduced more than 30 years ago.240 They are simply defined in terms of vertex-degrees ... 

Thus, equations (42) and (43) show that both Zagreb indices may be regarded as combinatorial quantities related to simple walks on molecular graphs. 

Gutman index = first Zagreb index Zagreb indices... 

Overall Zagreb indices, denoted by OM2, were defined as an extension of —> Zagreb indices as [Bonchev, 1997 Nikolic, Tolic et al, 2000]... 

Other overall indices, similar to overall Zagreb indices, were defined by using a different function that has terms inverse to those of OM2 these indices were denoted by ON and are defined as [Bonchev, 1999, 2000, 2001a, 2001b Bonchev and Trinajstic, 2001]... 

From these local invariants, Zagreb indices, —> connectivity-like indices, and —> Wiener-type indices were derived as... 

Generalized topological indices are calculated by using common formulas of topological indices, where the exponent, if any, is allowed to differ from the standard value (e.g., —1/2 in the Randic connectivity index). Examples of these are the variable Zagreb indices, —> generalized connectivity indices, and —> generalized Wiener indices. 

Variable connectivity index, variable Balaban index, and variable Zagreb indices for 2-pentanol. A(x, y) and D(x, y) are the variable augmented adjacency matrix and the variable augmented distance matrix, respectively. VS, indicates the matrix row sums x and y are the variable parameters for carbon and oxygen atom, respectively. 

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