Is Cyanide Really a Strong-Field Ligand?

摘要

Opin states of transition-metal complexes are controlled by the number and nature of the ligands. In particular, first-row metal ions, such as Cr~(n+), Mn~(n+), Fe~(n+), and Co~(n+), adopt a variety of electronic structures, including high-spin, low-spin, and in some cases intermediate-spin states.'11 Furthermore, each spin state could have different electron configurations, as exemplified most explicitly in low-spin iron(III) porphyrins; they adopt either (d_(xy))(d_(xz),d_(yz)) or (d_(xz),d_(yz))(d_(xy)) configurations.