Chemistry of Tantalum and Niobium Fluoride Compounds

2. Synthesis of tantalum and niobium fluoride compounds

2.1. Aqueous solutions

2.2. Non-aqueous solutions

2.3. Interactions with TaF5 and NbF5

2.4. Synthesis of fluoride compounds using NbO2F and TaO2F

2.5. Hydrofluoride synthesis of niobium and tantalum compounds

3. Crystal chemistry of tantalum and niobium fluoride compounds

3.1. Island-type structure compounds

3.2. Compounds with chain-type structure

3.3. Compounds with layered-type structure

3.4. Compounds with framework-type

3.5. Compounds with coordination-type structure

3.6. Crystal chemical classification

4. Tantalum and niobium complexes in fluoride solutions

4.1. Niobium containing solutions

4.2. Tantalum containing solutions

5. Tantalum and niobium complexes in fluoride melts

5.1. Preliminary notes

5.2. Melting diagrams

5.3. Physicochemical properties

5.4. Vibration spectroscopy of fluoride melts

5.5. Main conclusions

6. Thermal properties and decomposition of tantalum-and niobium-containing fluoride compounds

6.1. Impact of temperature on solid fluoride complexes

6.2. Melting processes

6.3. Thermal decomposition of oxyfluoroniobates

6.4. Gaseous components

6.5. Main conclusions

7. Ferroelectric properties of niobium and tantalum fluoride compounds

7.1. General notes

7.2. Compounds derived from lithium metatantalate

7.3. Spontaneous polarization and non-linear optic effect in niobium and tantalum fluoride compounds

7.4. Piezoelectric, pyroelectric and related properties in M5Nb3OF18 compounds

8. Fluorine chemistry in the processing of tantalum and niobium

8.1. General notes

8.2. Raw material decomposition

8.3. Liquid-liquid extraction

8.4. Preparation of tantalum and niobium oxides

8.5. K salt production

8.6 The production of tantalum and niobium metals by reduction of fluoride melts

9. Main principals of the chemistry of tantalum and niobium fluoride compounds

Appendix (X ray powder diffraction data of some important tantalum and niobium fluoride compounds)

Niobium-containing compounds

Tantalum-containing compounds