Another method is based on homologization of diynes by transition metals ( through zirconacyclopentadienes ) Functionalization of pentacene has allowed for control of the solid-state packing of this chromophore.
2.
It also gained homologization for rallying in Sweden's Standard-B class ( minimum weight of 15 kg / ps ) in the spring of 1977, with some minor modifications to the engine and gearing.