The CASINO forum

Dear fellow CASINO users, I am writing this post to make anybody who might be using numerical orbitals in their QMC calculations aware of a bug we (myself and Neil Drummond) have found. If you have compiled CASINO on a version of gfortran >= 4.9 , and are using numerical orbitals in DMC, there is a ...

Dear Nguyen_Oanh, The density of states for a crystalline material would be calculated from a set of orbitals on a (hopefully very fine) mesh of k-point in an irreducible wedge of the Brillouin Zone. For a fixed density, these orbitals can be calculated and the DOS formed by taking some integral ove...

Dear Nguyen_Oanh, You need to decide what region you would like to plot in and what quantity you would like to plot. Say density for example, then you would write a plot_expval block like this %block plot_expval 3 10 10 10 v11 v12 v13 v21 v22 v23 v31 v32 v33 v41 v42 v42 %endblock plot_expval where v...

Dear Nguyen_Oanh, In some respects you are right - the manual says very little about how to calculate band gaps directly. However, the manual provides information on how one can (a) ADD/REMOVE electrons and (b) PROMOTE electrons. If you want to calculate a bandgap - firstly you should decide which o...

Dear Nguyen_Oanh, I think the answer to your question involves the way in which band-gaps are calculated in CASINO.The bandgap itself is not something you can access from the "plot_expval" utility. Band-gaps are obtained from total energy calculations made with different levels of excitati...

Katharina,

Obvious one - but does your Jastrow factor have anything non-linear with its optimizable flag set to "T"? Were you perhaps optimizing a cut-off?

Thanks, Ryan.