Structures of Complex Oxides

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Structures of Complex Oxides

• Multiple cations
• Perovskite ABO3
• Capacitors
• Spinel
• Magnetic properties

• Covalency
• Zinc blende
• Semiconductors
• Diamond
• Semiconductors
• Silicates
• Minerals

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Perovskite

• Perovskite ABO3 B ? boron
• A2B4O3 A3B3O3 A1B5O3
• CaTiO3 LaAlO3 KNbO3
• Occurs when RA RO and RA gt RB
• CN(Ti) 6
• CN(Sr)
• CN(O) 2Ti 4Sr
• CNs make sense?
• Example SrTiO3
• RTi 0.61 Å
• RSr 1.44 Å
• RO 1.36 Å

above/below
12
RTi/RO 0.45 RSr/TO 1.06
http//abulafia.mt.ic.ac.uk/shannon/ptable.php
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Tolerance factor
close-packed directions
A
Ba A Zr B
B
4
(No Transcript)
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extent of periodicity
polycrystalline
single crystal