LaFe_(11.5)Si_(1.5)中的磁不稳定性

Magnetovolume instability in compound LaFe_(11.5)Si_(1.5)

通过对LaFe11.5Si1.5化合物进行自旋极化和固定磁矩(FSM)的能带计算,发现LaFe11.5Si1.5化合物具有磁不稳定性的特征,无磁态和铁磁态的能量差别很小,FSM计算表明LaFe11.5Si1.5化合物具有低自旋态和高自旋态的双磁性态特征,在一定条件下能够在两磁性态之间发生变磁转变.通过计算的结果,定性地分析了实验上所观察的一些现象.

In order to investigate the magnetovolume instability in compound LaFe11.5Si1.5, we employed first-principles electronic-structure calculations by using a full-potential linearized-augmented-plane-wave method within the generalized-gradient approximation. The total energies of nonmagnetic and ferromagnetic states were calculated by spin-polarization approach and the calculated results showed that there is little difference between them. The fixed-spin-moment calculation confirmed that the metamagnetic transition was associated with low-spin-high-spin transition in compound LaFe11.5Si1.5. Based on the calculated results, we could explain qualitatively some of the experiment results.