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Updated: Aug 12, 2026

Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions
Published on: June 13, 2015
Partial Quenching of Parametrical Tetragonality of a Chromium(III) Complex by Pressure Tuning
C. E. Schäffer1, J. M. Lang, H. G. Drickamer
1School of Chemical Sciences and The Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801.
Abstract:
The ligand-field spectrum of [Cr(NH(3))(4)F(2)]AsF(6) has been pressure-tuned up to 100 kbar. The parametrical analysis shows that the absolute values of the two independent tetragonalities of the chromophoric ion both decrease with increasing isotropic pressure so that the molecular ion becomes more isotropic. Moreover, the Cr-N single bonds appear to be more compressible than the Cr-F bonds, for which it is parametrically clear that they have a partial multiple-bond character. While the spectrochemical parameter for F(-), Delta(F), increases with pressure, its two components Delta(sigma)(F) and Delta(pi)(F) decrease. It is confirmed that nephelauxetism increases with pressure.
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