Structure of hexakis(acetonitrile)nickel(II) hexafluoroantimonate(V)

Abstract

Abstract. [Ni(NCCH3)

X-ray Absorption Spectroscopy Study of the In-Solution Structure of Ni2+, Co2+, and Ag+ Solvates in Acetonitrile Including Multiple Scattering Contributions

“…This geometry was also found in an X-ray absorption study of a solution of Ni 2+ cations in acetonitrile, which provided a value for the Ni 2+ −N distance of 2.07 Å . Similarly, in a X-ray diffraction study of the crystalline compound [Ni(CH 3 CN) 6 ](SbF 6 ) 2 , the basic units were octahedral arrangements of solvent molecules around the nickel cation being the Ni 2+ −N distances 2.075(3) Å . NMR studies of Co 2+ acetonitrile solutions pointed as well to octahedral coordination, this geometry was confirmed by an X-ray absorption study in acetonitrile solution which provided a value of 2.11 Å for the C−N distance …”

“…Concerning the coordination angle formed by the solvent molecules and the central cation, as stated before, there are insufficient constraints provided by the data to determine its value accurately, and satisfactory values were found to range from 160° to 180°. Thus, the slight disagreements found between the experimental spectra and the fit in Ni 2+ and Co 2+ spectra (see Figure ) could be due to small deviations from the assumed value of 180°, such as that found in the crystalline compound [Ni(CH 3 CN) 6 ](SbF 6 ) 2 , where the Ni−N−C angle determined by means of XRD is 175.5(3)° …”

“…(a) Ni 2+ and Co 2+ Acetonitrile Solvates Analysis. Taking into account previous results of related systems, − an octahedral configuration of the acetonitrile molecules around the central cation was considered to calculate the significant contributions to the absorption spectra. Likewise, considering the high amplitude of the second peak in the FT, a linear arrangement of the nitrogen and carbon atoms was assumed and, in a first approach, only N and C atoms from the cyanide group were taken into account.…”

Investigation of the Ligand Exchange Behavior of Square‐Planar Nickel(II) Complexes by X‐ray Absorption Spectroscopy and X‐ray Diffraction

“…The structural parameters determined from the Ni K-edge EXAFS spectrum agree quite well to the acetonitrile complex [Ni(CH 3 CN) 6 ]-SbF 6 , [50] in which the acetonitrile molecules have a bridging position between the Ni atoms. 1 H NMR experiments on the acetonitrile product have proved the splitting of the bpy and the mesityl ligand (as mesitylene), the latter seems to be a pre-requisite to the formation of octahedral species.…”

Catalyst Deactivation by β‐Hydride Elimination: Olefin and Alkyne Insertion into Arenido–Nickel(II) Bonds

“…[13] The distance of the Ni-N bond in [Ni(MeCN) 6 ] 2+ ranges from to 2.07 to 2.08 Å with various counteranions. [14,15] The coordination bond between nitrogen and nickel is the only position in this framework, which is flexible enough to be adjusted. Apparently, to achieve the required space for the two C 3 F 7 chains in the comb of the framework the bond between nickel and the nitrogen atom of the nitrile group is elongated.…”