T.P. is a professor in the School of Chemistry at the University of Hyderabad, India. His research interests are: molecular materials: semiconductors, composite ionic conductors, charge transfer ion radical solids, graphite intercalation compounds, low-dimensional coordination complexes, molecular nonlinear optical materials, thin films; computational chemistry; quantum chemical studies of organic spin systems, topological rules for spin state predictions, hyperpolarisability calculations; chemical graph theory; similarity, unusual graph degeneracy problems.