The adsorption and self-assembly of manganese phthalocyanine (MnPc) molecules on Bi(1 1 1) are investigated by means of low-temperature scanning tunneling microscope (STM). At low temperature (4.6K), isolated MnPc molecules adsorb flatly on Bi(1 1 1) with the two opposing lobes aligned in the direction of surface base vectors. When temperature is increased to 78K, individual MnPc molecules rotate around the central Mn ion until they meet other MnPc molecules forming self-assembled structures. With the coverage increasing, MnPc molecules show a structural evolution from single molecules to molecular chains, and finally to 2-D domains. In particular, high-resolution STM images reveal there are two mirrored molecular chains with alternating arrangement in the 2-D domains. Annealing the sample to room temperature leads to a phase separation such that each molecule chains appeared only in the respective domains. (C) 2014 Elsevier B.V. All rights reserved.