Experimental and First-Principles NMR Analysis of Pt(II) Complexes With O,O'-Dialkyldithiophosphate Ligands.
Polycrystalline bis(dialkyldithiophosphato)Pt(II) complexes of the form [Pt{S2P(OR)2}2] (R = ethyl, iso-propyl, iso-butyl, sec-butyl or cyclo-hexyl group) were studied using solid-state31P and195Pt NMR spectroscopy, to determine the influence of R to the structure of the central chromophore. The measured anisotropic chemical shift (CS) parameters for31P and195Pt afford more detailed chemical and structural information, as compared to isotropic CS and J couplings alone. Advanced theoretical modeling at the hybrid DFT level, including both crystal lattice and the important relativistic spin-orbit effects qualitatively reproduced the measured CS tensors, supported the experimental analysis, and provided extensive orientational information. A particular correction model for the non-negligible lattice effects was adopted, allowing one to avoid a severe deterioration of the195Pt anisotropic parameters due to the high requirements posed on the pseudopotential quality in such calculations. Though negligible differences were found between the195Pt CS tensors with different substituents R, the31P CS parameters differed significantly between the complexes, implying the potential to distinguish between them. The presented approach enables good resolution and a detailed analysis of heavy-element compounds by solid-state NMR, thus widening the understanding of such systems.
NMR Research Unit, University of Oulu , P.O. Box 3000, FI-90400 Oulu, Finland.
Juho
J
Roukala
Department of Physics, The University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.
Simon T
ST
Orr
Department of Physics, The University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.
John V
JV
Hanna
NMR Research Unit, University of Oulu , P.O. Box 3000, FI-90400 Oulu, Finland.
Juha
J
Vaara
Institute of Geology and Nature Management, Far Eastern Branch of the Russian Academy of Sciences , Ryolochny Lane 1, Blagoveshchensk 675000, Amur Region, Russia.
Alexander V
AV
Ivanov
Department of Physics, The University of Warwick , Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.|Chemistry of Interfaces, Luleå University of Technology , SE-971 87, Luleå, Sweden.
Oleg N
ON
Antzutkin
NMR Research Unit, University of Oulu , P.O. Box 3000, FI-90400 Oulu, Finland.
Perttu
P
Lantto