[Pw_forum] Re: cut-off radius for radial integrations

[Paolo Giannozzi]

On Thursday 24 February 2005 09:01, Virginie Quequet wrote:

> I mean that the two pseudo-potentials for Si given with espresso
> SiPBE_nc.UPF and Si.vbc.UPF have their non-local part cut at 10 a.u.
> (only 957 points on a mesh of 1141 for SiPBE_nc.UPF and only 359 
> points on a mesh of 431 for Si.vbc.UPF). So when I use one of this
> pseudo-potential and change rcut, nothing happens, but if I use instead
> a pseudo with non-local part cut at 80 a.u., I see the difference.

the above means nothing to me. If you use a different pseudo, you
get different results. A pseudo cannot have "a non-local part cut at
80 a.u." : the nonlocal part is, by construction, zero beyond the
matching radius, i.e. a few a.u. . The local part has a known behavior
(-Z/r) at large r and this is accounted for analytically. Please explain
EXACTLY what you are doing (i.e. in such a way that one can reproduce
it)

Paolo
-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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