Skip to Content.
Sympa Menu

forum - Re: [abinit-forum] optimization problem

forum@abinit.org

Subject: The ABINIT Users Mailing List ( CLOSED )

List archive

Re: [abinit-forum] optimization problem


Chronological Thread 
  • From: Emmanuel Arras <emmanuel.arras@cea.fr>
  • To: forum@abinit.org
  • Subject: Re: [abinit-forum] optimization problem
  • Date: Tue, 23 Sep 2008 18:30:59 +0200

You have a problem with periodicity :
acell 34.0d0 34.0d0 5.5d0 angstrom

so your c axis has a lenght of 5.5 Angstrom whereas the max z coordinate of your atoms is 1.41 (and -1.41) angstrom.

Thus your acell should be
acell 34.0d0 34.0d0 4.23 angstrom

furthermore, 34 angstrom is indeed very big and your calculation may not run that easily.

Regards

Emmanuel ARRAS



Maryam jamali a écrit :
149732.44080.qm@web59613.mail.ac4.yahoo.com" type="cite">
 
Dear all,
 

To optimize my molecule (nanotube), I inserted its unit cell (32 atom) in super cell with dimension of 34 34 5.5 angstrom. When the job completed, I found that the structure was not optimized and the bond length between carbons was longer than a usual double bond (about 1.55 ang). What is the problem?

 

 Thank you in advance.

 

You can see the input as follows:

 

ixc 11

 

acell 34.0d0 34.0d0 5.5d0 angstrom

 

angdeg 90.0d0 90.0d0 90.0d0

ionmov 2

ntime 800

tolmxf 1.0d-5

ecut 22

natom 32

nstep 800

ntypat 1

toldfe 1.0d-5

typat 32*1

znucl 6

diemac 12

 

xangst 1.18992 2.87283 -0.70500

2.19875 2.19875 -1.41000

1.18992 2.87283 0.70500

2.19875 2.19875 1.41000

-1.18992    2.87283 -0.70500

0.00000 3.10943 -1.41000

-1.18992    2.87283 0.70500

0.00000 3.10943 1.41000

-2.87283    1.18992 -0.70500

-2.19875    2.19875 -1.41000

-2.87283    1.18992 0.70500

-2.19875    2.19875 1.41000

-2.87283    -1.18992    -0.70500

-3.10943    0.00000 -1.41000

-2.87283    -1.18992    0.70500

-3.10943    0.00000 1.41000

-1.18992    -2.87283    -0.70500

-2.19875    -2.19875    -1.41000

-1.18992    -2.87283    0.70500

-2.19875    -2.19875    1.41000

1.18992 -2.87283    -0.70500

0.00000 -3.10943    -1.41000

1.18992 -2.87283    0.70500

0.00000 -3.10943    1.41000

2.87283 -1.18992    -0.70500

2.19875 -2.19875    -1.41000

2.87283 -1.18992    0.70500

2.19875 -2.19875    1.41000

2.87283 1.18992 -0.70500

3.10943 0.00000 -1.41000

2.87283 1.18992 0.70500

3.10943 0.00000 1.41000

 





Archive powered by MHonArc 2.6.15.

Top of Page