Mathematical descriptors of molecular structure, such as various topological indices, have been widely used in structure-property-activity studies (see [5, 6, 12]). Among the numerous topological indices considered in chemical graph theory, only a few have been found noteworthy in practical application (see [10]). One of these is the connectivity index or Randić index. The Randić index of an or...

Polynomial interpolation can be used to obtain closed formulas for topological indices of infinite series of molecular graphs. The method is discussed and its advantages and limitations are pointed out. This is illustrated on fullerenes C12k+4 and four topological indices: the Wiener index, the edge Wiener index, the eccentric connectivity index, and the reverse Wiener index. The results for th...

We give sharp upper bounds on the Zagreb indices and lower bounds on the Zagreb coindices of chemical trees and characterize the case of equality for each of these topological invariants.

Topological indices are one of the oldest and most widely used descriptors in Quantitative StructureProperties Relationvhips (QSPR). Amongst the topological indices used a,s descriptors in QSPIC., the Wienerindex is by far the most popular index. as it has been shown that the Wiener index has a strong correlationwith the chemical propenies of the compound.In this study, the relationship between...

Molecular lipophilicity was studied using salicylamide as a model drug. Log P value for the target compound was experimentally determined by the shake-flask method and calculated using nine different computer programs based on atom/fragment contributions, structural parameters, atom-type electrotopological-state indices and neural network modeling, or topological structure descriptors. Our anal...

Laplace operators perturbed by meromorphic potential on the Riemann and separated type Klein surfaces are constructed and their indices are calculated by two different ways. The topological expressions for the indices are obtained from the study of spectral properties of the operators. Analytical expressions are provided by the Heat Kernel approach in terms of the functional integrals. As a res...