Publisher Summary This chapter reviews the literature on solid-state cobalt-59 ( 59 Co) nuclear magnetic resonance (NMR) so as to complement the existing excellent reviews on solution-state work. A brief account of the recent progress in chemical shift interpretation and relaxation studies is presented, covering the relevant solution-state studies published in the 1990s, in which particular attention is given to controversial results. The chapter also summarizes the advances in the theoretical calculations of 59 Co NMR parameters. The focus is on what has been done for 59 Co rather than the “technical details” of the treatments. As very little has been reported for spin-spin coupling constants involving 59 Co nucleus, the solid-state data compilation was done only for chemical shifts and quadrupole coupling constants. The future trend will be to combine different strategies of solidstate and/or solution-state NMR to provide a unified description of the systems under investigation. In particular, it is anticipated that theoretical calculation will provide a new dimension in 59 Co NMR spectroscopy, enabling its application to more complicated systems.

Cobalt-59 NMR spectroscopy

A single-crystal X-ray diffraction study at 110 K and ab initio calculations up to the MP2/6-31G* level of theory showed that the ground state of P(NMe2)3 has Cs symmetry, with two different coordination geometries at the nitrogen atoms (pyramidal and planar). The calculated and experimentally determined geometries are in good agreement. Steric strain could be ruled out as the predominant factor causing the deviation from the expected C3 symmetry, because ab initio calculations on the model system P(NH2)3 (up to MP2/6-311G**) also indicate Cs symmetry for the ground-state structure, whereas calculations on N(NH2)3 have predicted this molecule to have C3 symmetry. The structure of the phosphorane H2CP(NMe2)3 has been elucidated by X-ray diffraction in the solid state (110 K) and by electron diffraction in the gas phase augmented by restraints derived from ab initio calculations up to the MP2/6-31G* level of theory. Solid-state and gas-phase structures are in good agreement showing again the Cs arrangement ...

Low Symmetry in P(NR2)3 Skeletons and Related Fragments: An Inherent Phenomenon

https://epub.uni-regensburg.de/13340/1/vogler48.pdf

Photochemistry of [MCo2(CO)8] (M = Zn, Cd, Hg) induced by metal to metal charge tranfer excitation

The synthesis and mass spectra of triaryl-gallium and -indium compounds

In the OSF(4)/Me(2)NSiMe(3) system besides the long known Me(2)NS(O)F(3) only the trisubstituted derivative is isolated as (Me(2)N)(3)SO(+)Me(3)SiF(2)(-) (3). Similar to (Me(2)N)(3)S(+)Me(3)SiF(2)(-) compound 3 is an excellent fluoride ion donor. With AsF(5) and HF the corresponding hexafluoroarsenate (Me(2)N)(3)SO(+)AsF(6)(-) (4) and the hydrogen bifluoride (Me(2)N)(3)SO(+)HF(2)(-) (5) are formed in almost quantitative yield. X-ray structure determinations of 3-5 surprisingly showed two different types of structures for the cation. In 3 and 5 this cation has C(3) symmetry, while in the hexafluoroarsenate 4 a (Me(2)N)(3)S(+)-like structure with C(s)() symmetry is determined. The experimental results for (Me(2)N)(3)SO(+) and (Me(2)N)(3)S(+) are compared with theoretical calculations for these cations and their isoelectronic neutral counterparts, the phosphorus amides (Me(2)N)(3)PO and (Me(2)N)(3)P, respectively.

T. B. Brill

Papers

Periodic trends in metal-metal bond character based on cobalt-59 nuclear quadrupole resonance spectroscopy

Periodic trends in metal-metal bond character based on cobalt-59 nuclear quadrupole resonance spectroscopy