Premium
Square‐Planar Pt II versus Octahedral Pt IV Halido Complexes: 195 Pt NMR Explained by a Simple Empirical Approach
Author(s) -
Benedetti Michele,
De Castro Federica,
Fanizzi Francesco P.
Publication year - 2016
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201600573
Subject(s) - chemistry , octahedron , crystallography , ionic radius , nmr spectra database , radius , analytical chemistry (journal) , crystal structure , spectral line , ion , physics , computer security , organic chemistry , chromatography , astronomy , computer science
In this work, we show by a simple empirical approach that a linear relationship between observed 195 Pt NMR frequencies and the overall sum of the ionic radii of the coordinated halido ligands [Σ( r h )] exists in square‐planar Pt II complexes of the type [PtX n Y 4– n ] 2– (1 ≤ n ≤ 4; X, Y = Cl, Br, I). Another finding was that such square‐planar complexes could be empirically described as octahedral complexes, with the two lobes of the 5d z ² orbital above and below the coordination plane acting as two pseudo‐halido ligands, each showing a constant apparent radius of around 207 pm. According to our approach, the overall apparent radius of around 415 pm produces constant 195 Pt NMR shielding for all [PtX n Y 4– n ] 2– complexes of about 10450 ppm. This result is 1) consistent with the theoretically calculated overall 5d shell lone‐pair shielding observed in square‐planar Pt II with respect to octahedral Pt IV complexes and 2) almost coincident with the already measured chemical shift anisotropy (CSA) of the K 2 [PtCl 4 ] complex both in solution and in the solid state (single crystal).