The 1-D compound [Fe(L)(CN)2][Mn(hfac)2] (1), which adopts the -NC-Fe-CN-Mn- heterometallic structure, has been shown to exhibit light-induced excited spin-state trapping effects. After illumination, anti-ferromagnetic coupling was observed between the iron(II) (S = 2) and manganese(II) (S = 5/2) ions.