Metallodithiolate ligands are used to design heterobimetallic complexes by adduct formation through S-based reactivity. Such adducts of dinitrosyl iron were synthesized with two metalloligands, namely, Ni(bme-daco) and Va O(bme-daco) (bme-daco = bismercaptoethane diazacyclooctane), and, for comparison, an N-heterocyclic carbene, namely, 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (Imes), by cleavage of the (mu-I)(2)[Fe(NO)(2)](2) dimer of electronic configuration {Fe(NO)(2)}(9) (Enemark-Feltham notation). With Fe(NO)(2)I as Lewis acid acceptor, 1:1 adducts resulted for both the IMes center dot Fe(NO)(2)I, complex 2, and V O(bme-daco)center dot Fe(NO)(2)I, complex 4. The NiN2S2 demonstrated binding capability at both thiolates, with two Fe(NO)(2)I addenda positioned transoid across the NiN2S2 square plane, Ni(bme-daco)center dot 2(Fe(NO)(2)I), complex 3. Enhanced binding ability was realized for the dianionic vanadyl dithiolate complex, [Et4N](2)[V O(ema)], (ema = N,N'-ethylenebis(2-mercaptoacetamide)), which, unlike the neutral (V O)N2S2 demonstrated reactivity with the labile tungsten carbonyl complex, cis-W(CO)(4)(pip)(2), (pip = piperidine), yielding [Et4N](2)[V O(ema)W(CO)(4)], complex 1, whose v(CO) IR values indicated the dianionic vanadyl metalloligand to be of similar donor ability to the neutral NiN2S2 ligands. The solid-state molecular structures of 1-4 were determined by X-ray diffraction analyses. Electron paramagnetic resonance (EPR) measurements characterize the {Fe(NO)(2)}(9) complexes in solution, illustrating superhyperfine coupling via the I-127 to the unpaired electron on iron for complex 2. The EPR characterizations of 3 [Ni(bme-daco)center dot 2(Fe(NO)(2)I] and 4 [V O(bme-daco)center dot Fe(NO)(2)I] indicate these complexes are EPR silent, likely due to strong coupling between paramagnetic centers. Within samples of complex 4, individual paramagnetic centers with localized superhyperfine coupling from the V-51 and I-127 are observed in a 3:1 ratio, respectively. However, spin quantitation reveals that these species represent a minor fraction (<10%) of the total complex and thus likely represent disassociated paramagnetic sites. Computational studies corroborated the EPR assignments as well as the experimentally observed stability/instability of the heterobimetallic DNIC complexes.