A new hetero-metal 2-dimensional (2D) spin-crossover complex, {[Fe-II(3-Fpy)(2)][Au-I(CN)(2)](2)}(n) (3-Fpy = 3-fluoropyridine) has been synthesized and characterized crystallographically and magnetically. The complex consists of an octahedral Fe ion and a mononuclear [Au-I(CN)(2)](-) unit with a linear coordination geometry which combine to form an infinite 2D structure. The spin transition observed for this complex is accompanied by a drastic and reversible change of color from blue to purple.