Spectral Analysis of Bis(N,N-diisopropyldithiocarbamato)nitrosyliron, Fe(NO)[S₂CN(CH(CH₃)₂)₂]₂, and Preparation and Crystal Structure of Its Cobalt Analogue


The title FeNO complex was previously shown to have a linear Fe-N-O linkage, perpendicular to the S4 plane of the dithiocarbamate ligands. Its infrared and ESR spectra are now reported, including those of the complex doped in its CoNO analogue. The cobalt complex is “d8” or Co-N-O8 and diamagnetic while the iron complex is “d7” or Fe-N-O7 and the magnetic susceptibility shows that it has one unpaired electron per molecule as expected. Although the iron and cobalt complexes are isomorphous, they exhibit an important structural difference, which demonstrates the importance of crystal structures in making detailed comparisons between isomorphous compounds. Crystal data for [Co(NO)(i-Prdtc)2]: space group P21/n, Z = 4, a = 9.252 (3) Å, b = 17.189 (2) Å, c = 14.018 (7) Å, β = 106.81 (7)°, V = 2134 Å3, R = 6.5%, Rw = 7.0%, 1819 reflections. The crystal structure of the cobalt complex reveals this to possess a bent Co-N-O linkage (∼129°). This means that the doped-sample spectra may pertain to a modified form of the iron complex, one having a bent Fe-N-O linkage. The solid-state ESR of the pure, known linear, Fe-N-O complex at 295 K gives g = 2.045. In solution, where Fe-N-O could be linear or bent, g = 2.047 and A for the 14N hyperfine is 14.4 G, while for the compound doped in the diamagnetic cobalt complex 〈g〉 = 2.047 (gx = 2.054, gy = 2.050, gz = 2.037) and 〈A〉 = 13.92 G (Ax = 12.5, Ay = 13.0, Az = 16.25 G). © 1983 American Chemical Society.



Document Type

Article - Journal

Document Version


File Type





© 1983 American Chemical Society (ACS), All rights reserved.