[Wien] Can w2web see symmetry?

[Peter Blaha]

Yes, WIEN2k detects symmetry, but only if it is EXACTLY present !!

There's no z mirror in your struct file!

 > ATOM  -2: X=0.32907000 Y=0.00000000 Z=0.20202000
 > ATOM  -8: X=0.32907000 Y=0.00000000 Z=0.79799000


Am 01.01.2013 14:19, schrieb John Rundgren:
> The following case.struct file shows a UC for a surface slab (a periodic
> repetition of atoms and gap i the z direction). The UC contains 9 atomic
> layers; it has sgroup 157 P31m with 6 xy symmetries.
>
> The slab is designed with a z mirror symmetry as is shown by XCrySden.
> Actually UC fulfills sgroup 189 P-62m with 12 symmetries. I know by
> accident in this particular case.
>
> Does w2web not always detect the complete symmetry of a given
> case.struct? A question about speed of calculation.
>
> Is there a general rule for extending sgroup A with N xy symmetries to
> sgroup B with N xy symmetries + 1 z mirror? A question typic of surface
> physics.
>
> Best regards, John Rundgren
>
> Cl-Ru0001
> H   LATTICE,NONEQUIV.ATOMS   9  157 P31m
> MODE OF CALC=RELA unit=bohr
>    8.856390  8.856390 59.832509 90.000000 90.000000120.000000
> ATOM  -1: X=0.00000000 Y=0.00000000 Z=0.26312000
>            MULT= 1          ISPLIT=15
> Cl         NPT=  781  R0=.000100000 RMT=   2.15000   Z:  17.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -2: X=0.32907000 Y=0.00000000 Z=0.20202000
>            MULT= 3          ISPLIT=15
>        -2: X=0.00000000 Y=0.32907000 Z=0.20202000
>        -2: X=0.67093000 Y=0.67093000 Z=0.20202000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -3: X=0.67093000 Y=0.00000000 Z=0.13571000
>            MULT= 3          ISPLIT=15
>        -3: X=0.00000000 Y=0.67093000 Z=0.13571000
>        -3: X=0.32907000 Y=0.32907000 Z=0.13571000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -4: X=0.33333333 Y=0.00000000 Z=0.06761000
>            MULT= 3          ISPLIT=15
>        -4: X=0.00000000 Y=0.33333333 Z=0.06761000
>        -4: X=0.66666667 Y=0.66666667 Z=0.06761000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -5: X=0.33333333 Y=0.33333333 Z=0.00000000
>            MULT= 3          ISPLIT=15
>        -5: X=0.66666667 Y=0.00000000 Z=0.00000000
>        -5: X=0.00000000 Y=0.66666667 Z=0.00000000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -6: X=0.33333333 Y=0.00000000 Z=0.93239000
>            MULT= 3          ISPLIT=15
>        -6: X=0.00000000 Y=0.33333333 Z=0.93239000
>        -6: X=0.66666667 Y=0.66666667 Z=0.93239000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -7: X=0.67093000 Y=0.00000000 Z=0.86429000
>            MULT= 3          ISPLIT=15
>        -7: X=0.00000000 Y=0.67093000 Z=0.86429000
>        -7: X=0.32907000 Y=0.32907000 Z=0.86429000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -8: X=0.32907000 Y=0.00000000 Z=0.79799000
>            MULT= 3          ISPLIT=15
>        -8: X=0.00000000 Y=0.32907000 Z=0.79799000
>        -8: X=0.67093000 Y=0.67093000 Z=0.79799000
> Ru         NPT=  781  R0=.000010000 RMT=   2.45000   Z:  44.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
> ATOM  -9: X=0.00000000 Y=0.00000000 Z=0.73688000
>            MULT= 1          ISPLIT=15
> Cl         NPT=  781  R0=.000100000 RMT=   2.15000   Z:  17.00000
> LOCAL ROT MATRIX:    1.0000000 0.0000000 0.0000000
>                       0.0000000 1.0000000 0.0000000
>                       0.0000000 0.0000000 1.0000000
>     0      NUMBER OF SYMMETRY OPERATIONS
>
> _______________________________________________
> Wien mailing list
> Wien at zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
>

-- 
-----------------------------------------
Peter Blaha
Inst. Materials Chemistry, TU Vienna
Getreidemarkt 9, A-1060 Vienna, Austria
Tel: +43-1-5880115671
Fax: +43-1-5880115698
email: pblaha at theochem.tuwien.ac.at
-----------------------------------------