On the origin of 13C and 14N hyperfine interactions in [Co(CN)6]4− and [Rh(CN)6]4− complexes in KCl host lattice

Ab-initio ROHF, PUHF and PUHF-MP2 calculations of 13C and 14N hyperfine interactions for the [Co(CN)6]4− and [Rh(CN)6]4− complexes in the KCl host lattice were performed and compared to experimental results. The host lattice was represented by a set of 80 potentials located at the ion positions, leading to a consistent picture of the complex electronic structure. A detailed analysis of each molecular orbital contribution shows that collective effects are very important and must be considered to achieve a realistic description of this property.