[Wien] trial energy El in case.in1

[Peter Blaha]

> I am trying to understand better the file case.in1 (or case.in1c) for lapw1.
> 
> In the user's guide (page 89), it states "If the same l value is specified
> twice, local orbitals are added to the (L)APW basis. The first energy (E1)
> is used for the usual LAPW's and the second energy (E2) for the LOs, which
> are formed according to (see equ. 2.7): u_E1+ dot{u}_{E1} + u_E2."
> 
> I understand this for the LAPW+LO basis by looking the form shown in equ.2.7.
> However, for APW+lo, as shown in Equ. 2.9,  the local orbital involves 
> only one energy
> parameter. So when the same l value is specified twice for the APW+lo in
> the case.in1 (or case.in1c), does it mean the first energy (E1) is used in
> the usual APW, i.e., Equ. 2.8 for the
> same l value, while the second energy (E2) is actually representing the
> variable E_1,l in Equ. 2.9?

Your interpretation for LAPW and LOs is correct.

For APW we use "small" lo (not LO) and the energy parameter for the lo 
is the same as for the APWs (i.e. the first line). Of course, even for 
APW+lo we may have additional LOs (specified in the 2nd line).
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Peter Blaha
Inst. Materials Chemistry, TU Vienna
Getreidemarkt 9, A-1060 Vienna, Austria
Tel: +43-1-5880115671
Fax: +43-1-5880115698
email: pblaha at theochem.tuwien.ac.at
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