The tetrametallic, diamond-shaped heterometallic complexes of iron(II) and Cu(I), [eta(5)-C5H5Fe(CO)(mu-CN)(2)Cu(PCy3)(x)](2), where x = 1 or 2, have been synthesized and fully characterized. X-ray crystallography reveals the geometrics about the copper(I) centers to be trigonal (x = 1) and tetrahedral (x = 2). Although the Fe-C=N bond angles are nearly linear, the Cu-N=C angles deviate significantly from linearity.