Wüthrich K, Shulman R G, Wyluda B J, Caughey W S
Proc Natl Acad Sci U S A. 1969 Mar;62(3):636-43. doi: 10.1073/pnas.62.3.636.
The nuclear magnetic resonance (NMR) spectra at 220 Mc of cyanodeuteroporphyrin IX dimethyl ester iron (III), cyanoprotoporphyrin IX diethyl ester iron (III), and cyanoprotoporphyrin IX iron (III) in a mixed solvent of 80 per cent d(5)-pyridine and 20 per cent D(2)O have been measured. The resonances are assigned and, except for the ester alkoxy groups, are shown to be shifted by temperature-dependent hyperfine interactions with Fe (III). From the experiments, upper limits are placed upon the pseudocontact contributions, and values of the contact interactions are derived. Spin densities in carbon pi-orbitals are calculated from the contact shifts and discussed in terms of preliminary Hückel calculations.
已测量了在80% d(5)-吡啶和20% D₂O的混合溶剂中，氰基氘代卟啉IX二甲酯铁(III)、氰基原卟啉IX二乙酯铁(III)和氰基原卟啉IX铁(III)在220兆赫时的核磁共振(NMR)光谱。对共振进行了归属，并且除酯烷氧基外，显示出因与Fe(III)的温度依赖性超精细相互作用而发生位移。通过这些实验，确定了赝接触贡献的上限，并得出了接触相互作用的值。根据接触位移计算了碳π轨道中的自旋密度，并根据初步的休克尔计算进行了讨论。
