[Pw_forum] Atomic position for Ni-Al alloy with BCC structure
Dear Paul, ? I think one of your pseudopotential need to be change for conformity. I try to run pw.x for your input file and noticed that there is overlapping between the two atoms. This the program complained. It is as a result of this that you are only seeing one atom in the matrix. ? ? Adetunji Bamidele Ibrahim Department of physics,University of Agriculture, Abeokuta, Ogun State,Nigeria. From: Paul Funso To: "pw_forum at pwscf.org" Sent: Saturday, January 7, 2012 8:47 PM Subject: [Pw_forum] Atomic position for Ni-Al alloy with BCC structure Dear All, ?I am working on BCC NI-Al alloy, which has a CsCl structure with ibrav = 3 and atomic position 0 0 0 for Ni atom and? 0.5 0.5 0.5 for Al atom. I am using xcrysden to view the structure, I only see Ni atoms and with no Al atom in the matrix. Can anybody please tell me where I am going wrong. I have my input file below. ? ??? calculation='scf' ??? restart_mode='from_scratch', ??? pseudo_dir = '/home/adebambo/espresso-4.2.1/pseudo/', ??? outdir='./' ??? prefix='Ni-Al' ??? tstress = .true. ??? tprnfor = .true. ?/ ? ??? ibrav = 3, celldm(1) =5.44 nat= 2, ntyp= 2, ??? ecutwfc = 15, ecutrho = 300.0 ??? occupations='smearing', smearing='marzari-vanderbilt', degauss=0.05 ?/ ? ??? diagonalization='cg' ??? mixing_beta = 0.7 ?/ ATOMIC_SPECIES ?Ni 58.69? Ni.pz-nd-rrkjus.UPF ?Al 26.98? Al.pz-vbc.UPF ATOMIC_POSITIONS ?Ni? 0.00? 0.00? 0.00 ?Al? 0.50? 0.50? 0.50 K_POINTS (automatic) ?4 4 4? 0 0 0 Thanks. Adebambo Paul Olufunso? PhD student, Department of Physics, University of Agriculture Abeokuta, Nigeria. ___ Pw_forum mailing list Pw_forum at pwscf.org http://www.democritos.it/mailman/listinfo/pw_forum -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20120107/2e73e459/attachment.htm
[Pw_forum] Atomic position for Ni-Al alloy with BCC structure
CsCl has the simple cubic structure, so ibrav=1. It's only called "BCC" because the atoms are on the sites of the BCC lattice, so if you replace Al by Ni you'd get a BCC Ni structure. On 01/07/2012 02:47 PM, Paul Funso wrote: > Dear All, > I am working on BCC NI-Al alloy, which has a CsCl structure with ibrav > = 3 and atomic position 0 0 0 for Ni atom and 0.5 0.5 0.5 for Al atom. > I am using xcrysden to view the structure, I only see Ni atoms and with > no Al atom in the matrix. Can anybody please tell me where I am going > wrong. I have my input file below. > -- Michael Mehl Naval Research Laboratory Washington DC
[Pw_forum] Atomic position for Ni-Al alloy with BCC structure
Dear All, ?I am working on BCC NI-Al alloy, which has a CsCl structure with ibrav = 3 and atomic position 0 0 0 for Ni atom and? 0.5 0.5 0.5 for Al atom. I am using xcrysden to view the structure, I only see Ni atoms and with no Al atom in the matrix. Can anybody please tell me where I am going wrong. I have my input file below. ? ??? calculation='scf' ??? restart_mode='from_scratch', ??? pseudo_dir = '/home/adebambo/espresso-4.2.1/pseudo/', ??? outdir='./' ??? prefix='Ni-Al' ??? tstress = .true. ??? tprnfor = .true. ?/ ? ??? ibrav = 3, celldm(1) =5.44 nat= 2, ntyp= 2, ??? ecutwfc = 15, ecutrho = 300.0 ??? occupations='smearing', smearing='marzari-vanderbilt', degauss=0.05 ?/ ? ??? diagonalization='cg' ??? mixing_beta = 0.7 ?/ ATOMIC_SPECIES ?Ni 58.69? Ni.pz-nd-rrkjus.UPF ?Al 26.98? Al.pz-vbc.UPF ATOMIC_POSITIONS ?Ni? 0.00? 0.00? 0.00 ?Al? 0.50? 0.50? 0.50 K_POINTS (automatic) ?4 4 4? 0 0 0 Thanks. Adebambo Paul Olufunso? PhD student, Department of Physics, University of Agriculture Abeokuta, Nigeria. -- next part -- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20120107/7f206c19/attachment.htm
