Relaxation (ISIF = 2,3,4) significantly differs from literature (both theoretical and experimental)
Posted: Fri May 31, 2013 9:13 am
I'm trying to do a relaxation on both OsO2 and RuO2, which have the same crystal structure. However, resulting CONTCAR that I get is significantly different than the reported crystal structure that has been reported in literature, both experimental and theoretical.
For example, for RuO2, I have the POSCAR:
but it results in the CONTCAR
My INCAR is rather simple, but I have tried varying parameters, including ISIF to 2 and 4 (which obviously don't result in the same CONTCAR as above, but are similarish), IBRION=1,2, ISMEAR=-5,1,2. I even varied KPOINTS using both Mankhorst and Gamma.
And strangely, it often converges to the same, but wrong, CONTCAR.
I also got incorrect results when trying to model OsO2.
Do you have any suggestions on what might be going on or what I could try to check?
For example, for RuO2, I have the POSCAR:
Code: Select all
RuO2?crystal
4.56
1.0?0.0?0.0
0.0?1.0?0.0
0.0?0.0?0.693
2?4????????????!?Ru?O
Direct
0.0?0.0?0.0
0.5?0.5?0.5
0.3068?0.3068?0.5
0.6932?0.6932?0.5
0.8068?0.1932?0.5
0.1932?0.8068?0.5
but it results in the CONTCAR
Code: Select all
RuO2?crystal????????????????????????????
???4.56000000000000?????
?????1.0954835323609240???-0.0003499940062927????0.0000000000000000
????-0.0003499940062876????1.0954835323609342????0.0000000000000000
?????0.0000000000000000????0.0000000000000000????0.5793475491135363
???2???4
Direct
??0.0000000000000000??0.0000000000000000??0.0000000000000000
??0.5000000000000000??0.5000000000000000??0.5000000000000000
?-0.2305121913043273?-0.2305121913043273??0.5000000000000000
??1.2305121913043275??1.2305121913043346??0.5000000000000000
??0.7692025139789147??0.2307974860210851??0.5000000000000000
??0.2307974860210851??0.7692025139789146??0.5000000000000000
?
??0.00000000E+00??0.00000000E+00??0.00000000E+00
??0.00000000E+00??0.00000000E+00??0.00000000E+00
??0.00000000E+00??0.00000000E+00??0.00000000E+00
??0.00000000E+00??0.00000000E+00??0.00000000E+00
??0.00000000E+00??0.00000000E+00??0.00000000E+00
??0.00000000E+00??0.00000000E+00??0.00000000E+00
My INCAR is rather simple, but I have tried varying parameters, including ISIF to 2 and 4 (which obviously don't result in the same CONTCAR as above, but are similarish), IBRION=1,2, ISMEAR=-5,1,2. I even varied KPOINTS using both Mankhorst and Gamma.
And strangely, it often converges to the same, but wrong, CONTCAR.
I also got incorrect results when trying to model OsO2.
Do you have any suggestions on what might be going on or what I could try to check?