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Spectral moments of phenylenes
S Marković1, Z Marković, R I McCrindle
1Department of Chemistry and Physics, Technikon Pretoria, Arcadia, Republic of South Africa. MarkovicZ@TechPTA.AC.ZA
Journal of Chemical Information and Computer Sciences
|February 24, 2001
Summary
Spectral moments of molecular graphs and line graphs are linearly dependent for phenylenes. Using spectral moments of line graphs offers no advantage over molecular graphs for predicting heat of formation in phenylenes.
Area of Science:
- Computational chemistry
- Chemical graph theory
- Quantitative structure-property relationships (QSPR)
Background:
- Previous studies utilized spectral moments of line graphs for QSPR and QSAR.
- Research indicated no difference between molecular graph and line graph spectral moments for benzenoid hydrocarbons.
Purpose of the Study:
- To investigate spectral moments of molecular graphs (Mk) and line graphs (muk) for phenylenes.
- To determine the relationship between Mk and muk for phenylenes.
- To assess the utility of line graph spectral moments for predicting the heat of formation of phenylenes.
Main Methods:
- Calculation and comparison of spectral moments for molecular graphs and line graphs of phenylenes.
- Analysis of linear dependence between Mk and muk.
- Correlation analysis with heat of formation data.
Main Results:
- The first few Mk and muk of phenylenes depend on identical structural parameters.
- Spectral moments of molecular graphs and line graphs of phenylenes are proven to be linearly dependent.
- No advantage was found in using lower spectral moments of line graphs over molecular graphs for predicting the heat of formation of phenylenes.
Conclusions:
- The redundancy observed in benzenoid hydrocarbons also exists in phenylenes regarding spectral moments.
- Spectral moments of molecular graphs are sufficient for QSPR studies of phenylenes, similar to benzenoid hydrocarbons.
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