[Pw_forum] Possible bug in TB09 MetaGGA

[Pedro Miguel Castro Borlido]

Greetings,

    I understand that the implementation of the TB09 meta gga is done  
in Espresso
though Libxc, as described in the article by Germaneau and colleagues.
    However, while looking through the code it seems that at no point  
the c parameter
(equation 3 of PRL 102, 226401 (2009)) is set with  
xc_f90_mgga_x_tb09_set_par thus
leaving c equal to 1 by default (i.e. the original BJ is used).

   Could someone please check if this is actually a bug of if c is  
actually set?

Best regards,
Pedro Borlido

Friedrich-Schiller Universität Jena
Institut für Festkörpertheorie und -optik
Max-Wien-Platz 1
07743 Jena