*International Journal of Quantum Chemistry*The expected values of sum-connectivity, harmonic and symmetric division
indices in random phenylene chains

16 May 2020

18 May 2020

18 May 2020

29 May 2020

29 May 2020

29 May 2020

A special class of conjugated hydrocarbons known as phenylenes, which is
composed of a special arrangement of six- and four-membered rings. In
particular, any two six-membered rings (hexagons) are not adjacent, and
every four-membered ring(square) is adjacent to a pair of nonadjacent
hexagons. If each hexagon of phenylene is adjacent only to two squares,
then the obtained chain is called the phenylene chain. The main object
of this paper is to determine the expected values of the
sum-connectivity, harmonic, and symmetric division indices of this class
of conjugated hydrocarbons. The comparisons between the expected values
of these indices with respect to the random phenylene chains have been
determined explicitly. The graphical illustrations have been given in
terms of the differences between the expected values of these indices.