Spin-polarization-induced structural selectivity in Pd 3 X and Pt 3 X ( X=3d ) compounds
Abstract
Spin-polarization is known to lead to important {\it magnetic} and {\it optical} effects in open-shell atoms and elemental solids, but has rarely been implicated in controlling {\it structural} selectivity in compounds and alloys. Here we show that spin-polarized electronic structure calculations are crucial for predicting the correct
T=0
crystal structures for Pd
3
X
and Pt
3
X
compounds. Spin-polarization leads to (i) stabilization of the
L
1
2
structure over the
D
O
22
structure in Pt
3
Cr, Pd
3
Cr, and Pd
3
Mn, (ii) to the stabilization of the
D
O
22
structure over the
L
1
2
structure in Pd
3
Co and to (iii) ordering (rather than phase-separation) in Pt
3
Co and Pd
3
Cr. The results are analyzed in terms of first-principles local spin density calculations.