test example of SiC optimization

From NWChem

You are viewing a single post from the thread title above
Jump to: navigation, search

Click here for full thread
Just Got Here
Threads 2
Posts 2

When I tried to run the example "Optimizing a unit cell and geometry for Silicon-Carbide", first I got an error message to complain the lack of memory. After I increased it, the optimization converged, and got the following information

Lattice Parameters

     lattice vectors in a.u. (scale by  1.000000000 to convert to a.u.)

     a1=<   8.646  -0.000   0.000 >
a2=< -0.000 8.645 -0.000 >
a3=< -0.000 0.000 8.127 >
a= 8.646 b= 8.645 c= 8.127
alpha= 90.000 beta= 90.000 gamma= 90.000
omega= 607.4

My question is why the norm of a3 is not the same as the norm of a1. How can I force the optimization to keep the ratios between the norms of a1, a2, and a3 constant? In other words, I would like to optimization process to scale a1, a2, a3 by the same factor.

Other questions:

1. Where can I find all possible options for different directives?
  "set includelattice .true." only apprars in an example input file, but not in the section of "http://www.nwchem-sw.org/index.php/Release61:Top-level#SET"
other examples: set nwpw:stress_numerical .true. #currently only numerical stresses
set nwpw:psi_nolattice .true. # turns of unit cell checking for wavefunctions

Is there any list to tell users that those parameter can be set by "set nwpw:$$" for nwpw?

2. Where can I find the refence for "task band"? I can't find any relevant reference from documentation or the paper "NWChem: A comprehensive and scalable open-source solution for large scale molecular simulations"

3. I have used LAMMPS package. The documentation of LAMMPS is pretty easy to follow. Would you mind to take a look and revise the documentation which can include references and default settings?

Thank you in advance.

Edited On 2:31:02 PM PDT - Thu, May 2nd 2013 by Zhdsheng

Who's here now Members 0 Guests 0 Bots/Crawler 0

AWC's: 2.5.10 MediaWiki - Stand Alone Forum Extension
Forum theme style by: AWC