Homework #26 CHEM 404 Assigned April 13, 2020 Due April 16, 2020 The textbook has an abbreviated spectrochemical series on p. 396 of the Fourth Edition, or p. 389 of the Fifth Edition. CO, CN– > phen> NO2– > en > NH3 > NCS– > H2O > F– > RCO2– > OH– > Cl– > Br– > I– We covered in the video some influences (not quite rules) that determine whether a complex is high-spin or low-spin. These can be summarized in the following algorithmic flow-chart: Start Here 3d, 4d or 5d? 3d Ox state? III 4d or 5d Low spin II No Very weak ligand? Very strong ligand? No Yes Yes High spin The uncertain part of this flow chart is the “very” weak and “very” strong ligands. Ligands like CO and CN– are very strong; halides are very weak. Thus [Co(CN)6]4–, a CoII complex, is low spin, despite the 2+ oxidation state of Co. On the other hand, [CoF6]3–, a CoIII