Use this URL to cite or link to this record in EThOS:
Title: Synthesis and structural characterisation of mixed-metal oxide pigment systems
Author: Owens, Craig
ISNI:       0000 0001 3461 9416
Awarding Body: University of Southampton
Current Institution: University of Southampton
Date of Award: 2004
Availability of Full Text:
Access from EThOS:
Full text unavailable from EThOS. Please try the link below.
Access from Institution:
The synthesis and characterisation of the NaCaV1-xMnxO₄ (x = 0, 0.02, 0.04, 0.06, 0.08 and 1.0) system has been carried out. Structural characterisation was performed through the use of powder X-ray diffraction, powder neutron diffraction and UV-Visible spectroscopy. These techniques reveal that the MnO₄3- complex ion can be stabilised within the NaCaVO₄ structure by isotopic substitution of the VO₄3- unit. The MnO₄3- ion imparts it own coordination geometry upon the host lattice, with the effect of making the MO₄3- a more regular coordination environment. The limit of substitution occurs at x = 0.08. Degradation of the colour over time makes this system unsuitable for use as a pigment. The preparation of the solid solution Cu₂Al1-xGax11BO₅ has been successfully completed with colours ranging from dark intense green to a lighter olive green. Structural characterisation has utilised powder neutron diffraction and CIELab colour measurements. The replacement of Al3+ with Ga3+ enlarges the average metal-oxygen distances, which in turn alters the copper coordination and hence the observed colour. Cu₂Al₆11B₄O17 has been prepared by conventional solid state methods and has been structurally characterised using powder neutron diffraction. The crystal structure of cobalt pyroborate (Co₂B₂O₅) has been further refined using powder neutron diffraction. The structure of Co2.45BO₅ has been determined from a single crystal X-ray refinement and is shown to adopt the Ludwigite structure. The structure contains four distorted octahedral CoO₆ environments and planar BO₃ units.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID:  DOI: Not available