[Pw_forum] Error in routine mix_rho (1): negative dr2

[Paolo Giannozzi]

On Tue, 2013-05-07 at 16:40 -0400, Daniel Cesar wrote:

> Error in routine mix_rho (1):
> negative dr2
> 
> Running the same kind of calculation with quantum_espresso-4.3 I have
> not experienced this error. 

because the calculation of the error estimate with PAW was slightly
different in 4.3.2. After the error estimate was improved, occasionally
one finds that the error estimate, a positive-definite quantity, 
becomes negative. In the svn version we reverted to the old estimate,
while waiting for better ideas.

P.

-- 
Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222