[Pw_forum] RRKJ pseudopotentials and raman calculations

[Merlin Meheut]

Dear PWSCF users,

To be simple, I would like to know if there is a fundamental difference 
between rrkj pseudopotentials generated with the opium software and 
rrkj"us" pseudopotentials, such as the carbon pseudopotential 
C.pbe-rrkjus.UPF present on your website. Apparently, the former work 
for Raman calculations, on the same level as trouillier-martins, whereas 
the latter is considered as "ultrasoft" and therefore the calculation 
crashes.

For my use, these rrkj pseudopotentials are perfect, since they seem 
sufficiently accurate and soft, and permit (if it is not a trick) to 
make Raman calculations. Pure Trouillier-Martins are usually very hard 
if high-precision is needed.

Thanks in advance,

Merlin
(University of Toulouse, France)


-- 
Merlin Méheut
Maitre de conférences 
LMTG- Université Paul Sabatier Toulouse 3
14 avenue Edoaurd Belin
31400 Toulouse
tel: (+33)5 61 33 26 21
Fax: (+33) 5 61 33 25 60
Mobile: (+33) 6 34 67 57 02