Loughborough University
Leicestershire, UK
LE11 3TU
+44 (0)1509 263171
Loughborough University

Loughborough University Institutional Repository

Please use this identifier to cite or link to this item: https://dspace.lboro.ac.uk/2134/22158

Title: Piezochromism in nickel salicylaldoximato complexes: tuning crystal-field splitting with high pressure
Authors: Byrne, Peter J.
Richardson, Patricia J.
Chang, John
Kusmartseva, Anna F.
Allan, David R.
Jones, Anita C.
Kamenev, Konstantin V.
Tasker, Peter A.
Parsons, Simon
Keywords: High-pressure chemistry
Transition metals
X-ray diffraction
Issue Date: 2012
Publisher: © Wiley-VCH
Citation: BYRNE, P. ... et al., 2012. Piezochromism in nickel salicylaldoximato complexes: tuning crystal-field splitting with high pressure. Chemistry: a European journal, 18 (25), pp.7738-7748.
Abstract: The crystal structures of bis(3-fluoro-salicylaldoximato)nickel( II) and bis(3-methoxy-salicylaldoximato) nickel(II) have been determined at room temperature between ambient pressure and approximately 6 GPa. The principal effect of pressure is to reduce intermolecular contact distances. In the fluoro system molecules are stacked, and the Ni Ni distance decreases from 3.19 Å at ambient pressure to 2.82 Å at 5.4 GPa. These data are similar to those observed in bis(dimethylglyoximato) nickel(II) over a similar pressure range, though contrary to that system, and in spite of their structural similarity, the salicyloximato does not become conducting at high pressure. Ni-ligand distances also shorten, on average by 0.017 and 0.011 Å for the fluoro and methoxy complexes, respectively. Bond compression is small if the bond in question is directed towards an interstitial void. A band at 620 nm, which occurs in the visible spectrum of each derivative, can be assigned to a transition to an antibonding molecular orbital based on the metal 3d(x 2-y 2) orbital. Time-dependent density functional theory calculations show that the energy of this orbital is sensitive to pressure, increasing in energy as the Ni-ligand distances are compressed, and consequently increasing the energy of the transition. The resulting blueshift of the UV-visible band leads to piezochromism, and crystals of both complexes, which are green at ambient pressure, become red at 5 GPa.
Description: Closed access.
Sponsor: We thank EPSRC for funding.
Version: Published
DOI: 10.1002/chem.201200213
URI: https://dspace.lboro.ac.uk/2134/22158
Publisher Link: http://dx.doi.org/10.1002/chem.201200213
ISSN: 0947-6539
Appears in Collections:Closed Access (Physics)

Files associated with this item:

File Description SizeFormat
Byrne_et_al-2012-Chemistry_-_A_European_Journal.pdfPublished version776.23 kBAdobe PDFView/Open


SFX Query

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.