p-Terphenyl(PTP) is an aromatic hydrocarbon isomer, formed by three benzene rings in ortho position. Pure terphenyl is a white crystalline solid, insoluble in water. Though polychlorinated terphenyls were used as heat storage and transfer agents, p-terphenyl is currently under investigation as a material to be used in opto-electronic devices, such as organic LED devices (OLEDs) and currently used in laser dyes and sunscreen lotions.