Lycopene the structure of the molecule was determined by 1931. In its natural, all-"trans" form, the molecule is long and straight, constrained by its system of 11 conjugated double bonds. Each extension in this conjugated system reduces the energy required for electrons to transition to higher energy states, allowing the molecule to absorb visible light of progressively longer wavelengths. Lycopene absorbs all but the longest wavelengths of visible light, so it appears red. Plants and photosynthetic bacteria naturally produce all-"trans" lycopene. When exposed to light or heat, lycopene can undergo isomerization to any of a number of "cis"-isomers, which have a
Alumina effect pigment Alumina effect pigment An alumina effect pigment is a pearlescent pigment based on alumina (aluminium oxide). In the first step of the production process, AlO (Aluminium oxide) flakes with a very smooth surface are formed. The flakes are produced using a crystal growth process. They are formed in the corundum structure (α-AlO). The desired flake shape is achieved by controlled crystal growth in the axial and equatorial directions. The color purity and transparency of the effect pigments obtained by coating the AlO flakes with metal oxides can be attributed to the synthesis procedure yielding single-crystalline thin flakes The coating of