Coordination Chemistry Reviews 257 (2013) 564–578
Contents lists available at SciVerse ScienceDirect
Coordination Chemistry Reviews
journa l h o me page: www.elsevier.com/locate/ccr
Review
Electronic structure of [Ni(II)S
4
] complexes from S K-edge X-ray absorption
spectroscopy
Matt S. Queen
a
, Bradley D. Towey
a
, Kevin A. Murray
a
, Brad S. Veldkamp
b
, Harlan J. Byker
b
,
Robert K. Szilagyi
a,*
a
Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, United States
b
Pleotint, LLC, West Olive, MI 49460, United States
Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 565
2. Experimental techniques and computational methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567
2.1. Preparation of compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567
2.2. Sulfur K-edge X-ray absorption spectroscopy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567
2.3. XAS data normalization and fitting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 567
2.4. Electronic structure calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 568
3. Results and analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 568
3.1. S K-edge XANES analysis of [Ni(II)S
4
] complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 568
3.2. S K-edge XANES analysis of S ligands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
3.3. Development of S 1s → 3p transition dipole integrals for S-ligands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 571
3.4. Experimental S 3p contributions to the Ni S bonds in [Ni(II)S
4
] complexes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 573
3.5. Theoretical electronic structure of [Ni(II)S
4
] complexes using DFT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574
4. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 574
5. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 576
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577
Appendix A. Supplementary data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 577
a r t i c l e i n f o
Article history:
Received 20 March 2012
Received in revised form 25 July 2012
Accepted 28 July 2012
Available online 3 August 2012
a b s t r a c t
The nickel ion has a remarkably rich coordination chemistry among the first-row transition
metals. Complexes with sulfur containing ligands are particularly notable, since they can mani-
fest classical/metal-based (innocent) or inverted/ligand-based (non-innocent) behavior depending on
the chemical composition of the S-ligands and the coordination geometry. Using sulfur K-edge X-
ray absorption spectroscopy (XAS), we established a spectrochemical series for [Ni(II)S
4
] complexes
Abbreviations: XAS, X-ray absorption spectroscopy; XANES, X-ray absorption near-edge structure analysis (electronic structure); EXAFS, extended X-ray absorption
fine structure analysis (geometric structure); K-edge, X-ray excitation from core 1s level; RIXS, resonant inelastic X-ray scattering; EPR, electron-paramagnetic resonance
spectroscopy; ENDOR, electron-nuclear double resonance, advanced EPR spectroscopy; ESEEM, electron spin echo envelop modulation, advanced EPR spectroscopy; XPS,
X-ray photoelectron spectroscopy; DFT, density functional theory; GGA, generalized gradient approximation for considering 1st derivatives of electron density in DFT cal-
culations; metaGGA, extension of GGA with the 2nd derivatives of electron density; hybrid GGA, electron density functional that mix Hartree–Fock exchange formalism
with GGA exchange functional; hybrid metaGGA, electron density functional that mix Hartree–Fock exchange formalism with metaGGA exchange functional; HOMO, high-
est occupied molecular orbital; LUMO, lowest unoccupied molecular orbital; SUMO, singly unoccupied molecular orbital; Z
eff
(S), sulfur effective nuclear charge seen by a
given orbital; SPh
′
, aromatic thiolate ligand (actual composition: C6H4-Ph-S
-
); nbdt, norbornadithiolate ligand; edt, ethylene dithiolate ligand (simplest olefinic enedithi-
olate); dmedt, dimethylethylene dithiolate ligand (olefinic enedithiolate); CNedt, cyanoethylene dithiolate (conjugated olefinic enedithiolate); mnt, maleonitrile dithiolate
ligand (conjugated olefinic enedithiolate); bdt, benzene dithiolate ligand (aromatic enedithiolate); dtc, dithiocarbamate ligand (conjugated); ttctd, tetrathiocyclotetradecane
thiocrownether (aliphatic thioether); NPG, neopentylglycol solvent/ligand; GBL, -butyrolactone solvent/ligand; E
C
0
, energy position for the S 1s →continuum edge jump of
a coordination complex; E
L
0
, energy position for the S 1s →continuum edge jump of a free ligand salt; I
C
, coordination complex-based, S 1s →3p transition dipole integral
from independent spectroscopic technique; I
L
, hypothetical S 1s →3p transition dipole integral for a ligand not involved in covalent bonding; fwhh, full width at half-height,
line width of XAS features at half amplitude, eV; D0, normalized intensity or analytical area of an XAS peak, eV.
*
Corresponding author.
E-mail address: Szilagyi@Montana.EDU (R.K. Szilagyi).
0010-8545/$ – see front matter © 2012 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.ccr.2012.07.020