Sunscreen chemical. Computer graphic of a molecule of the sunscreen chemical 2-ethylhexyl trans-4- methoxycinnamate (C18.H26.O3). The atoms (spheres) of the molecule are colour-coded: carbon (purple), hydrogen (white) and oxygen (red). The conjugation (regular spacing of double bonds) found in this molecule means it is good at absorbing part of the damaging ultraviolet (UV) radiation in sunlight.