<p>Hi,</p>
<p>I have two questions regarding XAS calculations.</p>
<p>1. For a system whose ground state is non-magnetic, should the core-hole SCF calculation be spin-polarized? My understanding is that the excited state must be non-magnetic to conserve spin. Thus I would expect that the non-spin-polarized calculation is more physical, even though in my case it is higher in energy than the spin-polarized calculation. </p>
<p>2. From what I've read in the literature, in some systems core-holes are delocalized over two neighboring symmetry equivalent sites. Has anyone tried modeling this situation with xspectra? I could imagine that one might use a half core-hole PP at both sites instead of a full core-hole at one site.</p>
<p>Thanks in advance.</p>
<p>Max Radin</p>