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Internet Electronic Journal of Molecular Design - IEJMD, ISSN 1538-6414, CODEN IEJMAT
| ABSTRACT - Internet Electron. J. Mol. Des. June 2002, Volume 1, Number 6, 319-331 |
Optimum Structural Descriptors Derived from the Ivanciuc-Balaban Operator
Ovidiu Ivanciuc, Teodora Ivanciuc, Daniel Cabrol-Bass, and Alexandru T. Balaban
Internet Electron. J. Mol. Des. 2002, 1, 319-331
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Abstract:
Topological indices represent an important class of structural
descriptors, widely used in developing structure-property models, in
drug design, virtual synthesis, similarity and diversity assessment.
Because there is a considerable interest in deriving additional
topological indices for QSPR and QSAR models, we introduce in this
paper an extended Ivanciuc-Balaban operator. We consider that the
exponent -1/2 used in the standard formula of this operator may not be
the optimum for modeling some molecular properties, and we now
define a new formula containing an adjustable exponent that is
optimized for each investigated property. The Ivanciuc-Balaban
structural descriptors were computed for 134 alkanes C6-C10
from seven molecular matrices, namely adjacency A, distance D,
reciprocal distance RD, distance-path Dp, reciprocal
distance-path RDp, path Szeged Szp,
and reciprocal path Szeged RSzp matrix. Structural
descriptors derived from the new operator were tested in QSPR studies
for several alkane properties and we found that in most cases the
optimum value of the exponent is different from -1/2.
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