Catechin monomers, dimers, and trimers (oligomers) are colorless. Porins usually arrange themselves in membranes as trimers. This form is molecular, consisting of discrete trimers. At room temperature trimers and tetramers are the most likely structures. The reason for such a behaviour and the particular structure of trimers has been analyzed. Dimers, trimers, and tetramers involving KCC2 have been identified in brainstem neurons. Industrially, the most important nonenes are trimers of propene&colon; Tripropylene. Eight of these trimers are then arranged into a hollow truncated cube. Unstable dimers and trimers are initially formed. Native APOBEC3G is composed of monomers, dimers, trimers, tetramers, and higher order oligomers. The dithiobenzoate complexes [M(SCPh)] crystallizes as a trimers (M = Ni, Pd). However, the majority of barley blocks remain trimers and tetramers. In the unliganded enzyme, the two catalytic trimers are also in contact. Trimers of isocyanates are sometimes labeled as 2,4,6-trioxohexahydro-1,3,5-triazines. They typically contain formaldehyde and are composed of dimers and trimers of the main molecule.