[Wien] Alkali hydrides elastics constants

[Stefaan Cottenier]

> The problem we have is connected to calculation of elastic constants.
> Everything went fine with Li, Na and K cases, but We cannot obtain
> meaningful results for CsH and RbH.
>
> (...)
>
> Situation is far worse for RbH with large fluctuations for tetra and
> again weak sensibility for rhomb case.

Little chance it is the (only) source of your problem, but try to  
increase the separation energy for Rb from -7 to -8, in order to  
include the 3d states in the valence region. If they are in the core,  
the 4s is the only 'real' valence state, and with these 3d between -7  
and -8 that's on the limit to be very reliable.

Also check posts to this list few weeks ago on treating Cs (useful  
reply i.a. by Georg Madsen).

Stefaan


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