The Preparation and Properties of Some Complex Fluorides

Russell, David Robin (1963) The Preparation and Properties of Some Complex Fluorides. PhD thesis, University of Glasgow.

Abstract

A wide range of complex fluorides with the general formula ABFe, A being a univalent cation and B a quinquevalent element, has been prepared in an attempt to discover the chief factors influencing their solid state structures. New preparations have Been used for some complexes of this type and some previously unreported compounds have Been obtained; non-aqueous solvents such as sulphur dioxide and anhydrous hydrogen fluoride have Been found to be useful reaction media. The types of unit cell found amongst these complexes were examined using X-ray powder photography. With the structures of over eighty complex fluorides now available it has Been possible to draw a clearly defined relationship Between the size of the A and B ions and the structure which is adopted. To assist in the intexpretation and calculation of lattice constants from X-ray powder photographs, a series of programmes has Been written for the Ferranti Sirius computer. Included in the series are programmes to calculate sin 0 values and lattice spacings, least squares refinement of unit cell parameters with corrections for systematic errors, and an analytical routine to interpret the photograph of a substance with an unknown unit cell. The vibrational spectra of octahedral MFs n- anions have Been studied for a series of complex fluorides with known crystal structures, using far infra-red (1100-200 cm-1) spectroscopy. The splittings of the fundamental vibration frequencies have Been correlated with the type of octahedral distortion known to occur in these compounds. The visible and ultra-violet reflectance spectra of a similar series of octahedral MFe n- anions containing transition elements have been recorded. It has been possible to assign the absorptions observed to electronic transitions occurring between the partly filled d-levels of the metal according to the predictions of ligand field theory. Conclusions have been drawn on the nature of the fluoride ion as a ligand. Attempts have been made to extend the very limited number of known metal carbonyl fluorides by reacting metal fluorides with carbon monoxide at high pressures. Evidence was obtained for the possible existence of a ruthenium carbonyl fluoride, but the compound could not be obtained in sufficient quantity for characterisation. Reactions of the previously known carbonyl fluorides of platinum and rhodium were investigated and a phosphide adduct of the former prepared.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Inorganic chemistry
• Date of Award: 1963
• Depositing User: Enlighten Team
• Unique ID: glathesis:1963-79479
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 09:06
• Last Modified: 05 Mar 2020 09:06
• URI: https://theses.gla.ac.uk/id/eprint/79479