MTPPBr4 (M = Cu, Co, Ni, Zn) were synthesized. Their UV-visible spectra and cyclic voltammetry were determine The relative energy of frontier orbital of metalloporphyrins, which explained the characters of UV-visible spectra and electrochem., were calculated according to four orbital parameters. The crystal structure of NiTPPBr4 was determine by a CAD4 diffractometer. Crystallog. parameters were as follows: monoclinic, space group C2/c with a 2.6077(7), b 1.0414(4), c 1.9312(3) nm; b 137.1(7)? Z = 4, F(000) = 2048, final R = 0.067. This structure directly verified that electrophilic bromination occurred regiospecifically at the antipodal pyrrolenic ring of free base porphyrins.

Key words: ULTRAVIOLET SPECTROPHOTOMETRY, CRYSTAL STRUCTURE DETERMINATION, METAL COMPLEX, ELECTRONIC STRUCTURE, NICKEL COMPLEX, FRONTIER ORBITAL THEORY, REGIOSELECTIVITY, FUEL CELL