The research based on density functional theory was carried out using generalized gradient approximation (GGA) for full-structural optimization and the addition of the correlation effect (GGA +
U (Coulomb parameter)) in a double perovskite structure,
A2BB’O
6. According
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The research based on density functional theory was carried out using generalized gradient approximation (GGA) for full-structural optimization and the addition of the correlation effect (GGA +
U (Coulomb parameter)) in a double perovskite structure,
A2BB’O
6. According to the similar valance electrons between IIA(
s2) and IVA(
p2), IVA group elements instead of alkaline-earth elements settled on the
A-site ion position with fixed
BB' combinations as Cr
M (
M = Mo, Re and W). The ferrimagnetic half-metallic (HM-FiM) properties can be attributed to the
p-d hybridization between the Cr
d-
Mp and the double exchange. All the compounds can be half-metallic (HM) materials, except Si
2CrMoO
6, Ge
2CrMo and Ge
2CrReO
6, because the strong-correlation correction should be considered. For
M = W, only
A = Sn and Pb are possible candidates as HM materials. Nevertheless, an examination of the structural stability is needed, because Si, Ge, Sn and Pb are quite different from Sr. All compounds are stable, except for the Si-based double perovskite structure.
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