(Bu_4N)[Ni(dmit)2] was synthesized by substituting Zn2+ in (Bu_4N) _2[Zn(dmit)_2] with Ni2+ and by auto-oxidation in acetone solution. This simple method can be extended to synthesize other Z [ M ( dmit )2 ] type complexes and Z[M(dmit)2]2 type conductive complexes. Two crystalline phases of (Bu_4N) [Ni(dmit)_2] , namely triclinic P1-bar phase and monoclinic C2/c phase which has been proved new, were obtained. The crystalline data of the C2/c phase are: a =2.0191(2) nm, 6 = 1.3404(1) nm, c = 1.2141(1) nm, β= 105.554(8)°, F=3165.5(6) nm3, R =0.055, C2/c space group.

Key words: NICKEL COMPLEX, CRYSTAL STRUCTURE, XRD, QUATERNARY AMMONIUM COMPOUNDS