The ABINIT Users Mailing List ( CLOSED )

["Aldo Humberto Romero" <aromero@qro.cinvestav.mx>]

Well... with respect to YVO4, according to the ICSD database, it is
a crystal with space group 141.. using the ICSD cif file as input in Abinit,
you get exactly spg 141.. try the following
..

acell    1.0000000000E+00  1.0000000000E+00  1.0000000000E+00

rprim   -3.5550000000E+00  3.5550000000E+00  3.1400000000E+00
              3.5550000000E+00 -3.5550000000E+00  3.1400000000E+00
              3.5550000000E+00  3.5550000000E+00 -3.1400000000E+00

typat    1  2  3  3  1  2  3  3  3  3  3  3

xred    8.7500000000E-01  1.2500000000E-01  7.5000000000E-01
              6.2500000000E-01  3.7500000000E-01  2.5000000000E-01
              6.3500000000E-01  2.0080000000E-01  4.3420000000E-01
              2.6660000000E-01  2.0080000000E-01  6.5800000000E-02
              1.2500000000E-01  8.7500000000E-01  2.5000000000E-01
              3.7500000000E-01  6.2500000000E-01  7.5000000000E-01
              2.0080000000E-01  2.6660000000E-01  5.6580000000E-01
              2.0080000000E-01  6.3500000000E-01  9.3420000000E-01
              7.3340000000E-01  7.9920000000E-01  9.3420000000E-01
              3.6500000000E-01  7.9920000000E-01  5.6580000000E-01
              7.9920000000E-01  3.6500000000E-01  6.5800000000E-02
              7.9920000000E-01  7.3340000000E-01  4.3420000000E-01


Good luck

regards

-aldo.


PS Abinit follows definitions from the crystallographic tables...
therefore, if you
find the wrong symmetry, please check your definition against the tables.
If you
build a supercell, obviously you do not have the symmetries coming from
the real unit cell.


-> Dear   Quan Phung Manh and Bryce
-> Same problem, i am facing. My structure is YVO4 , which is I4/mmm but
-> according the output file, it is  space group P2 (#  3); Bravais mP
-> (primitive monocl.) even i have not specified that  chkprim is 0. please
-> guide ,How can i solve this problem ??
->  My input file is pasted below
-> Thanks
-> Dev
->
-> # Data common to the three different datasets
->
-> acell 13.451637476  13.451637476  11.885054518
-> angdeg  90 90 90
->
-> #Definition of the atom types
-> ntypat 3          # There r 3 type of atom
-> znucl 39 23 8          # The keyword "znucl" refers to the atomic number
-> of
-> the
->                   # possible type(s) of atom.  (39- Y, 23 -V  and 8-O)
->
->
-> #Definition of the atoms
-> natom 24
-> typat 1 1 1 1 2 2 2 2  3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
-> xangst
->              0.000000000   5.338725356    0.786162553
->              3.559150238   1.779575118    3.930812762
->              3.559150238   5.338725356    2.358487657
->              0.000000000   1.779575118    5.503137866
->              0.000000000   1.779575118    2.358487657
->              3.559150238   5.338725356    5.503137866
->              0.000000000   5.338725356    3.930812762
->              3.559150238   1.779575118    0.786162553
->              0.000000000   3.090765987    1.262891534
->              3.559150238   6.649916224    4.407541744
->              3.559150238   4.027534488    4.407541744
->              0.000000000   0.468384251    1.262891534
->              5.807109607   5.338725356    2.835216639
->              4.870341106   1.779575118    5.979866849
->              3.559150238   3.090765987    1.881758675
->              0.000000000   6.649916224    5.026408885
->              0.000000000   4.027534488    5.026408885
->              3.559150238   0.468384251    1.881758675
->              4.870341106   5.338725356    0.30943357
->              5.807109607   1.779575118    3.45408378
->              1.311190868   1.779575118    3.45408378
->              2.247959369   5.338725356    0.30943357
->              2.247959369   1.779575118    5.979866849
->              1.311190868   5.338725356    2.835216639
->
->
-> On Sat, Oct 24, 2009 at 8:31 PM, Quan Phung Manh
-> <manhquank9@gmail.com>wrote:
->
->> Dear Bryce
->>
->> I don't know how your full input is. But I think your problem comes from
->> the keyword: chkprim 0. You doubled the cell, then Abinit symmetry
->> finder
->> found that the unit cell is not primitive. The multiplicity is  2. The
->> use
->> of non-primitive unit cells is allowed only when the input variable
->> chkprim
->> is 0. I guess you used this keyword to pass the error. That why you had
->> P1.
->>
->> Regards.
->>
->> 2009/10/22 <bmeredig@gmail.com>
->>
->> Dear Abinit users,
->>>
->>> I'm having symmetry issues... I'm working with a distorted fluorite
->>> cell
->>> that
->>> should have I4/mmm symmetry. When I use these inputs:
->>>
->>> typat 1 2 2
->>> xred
->>> 0 0 0
->>> 0.25 0.25 0.25
->>> 0.75 0.75 0.75
->>> acell
->>> 1.0 1.0 1.0 angstrom
->>> rprim
->>> 0 2.785 2.745
->>> 2.785 0 2.745
->>> 2.785 2.785 0
->>>
->>> The symmetry finder gives me, correctly, I4/mmm. However, when I simply
->>> double
->>> the cell along the c direction so:
->>>
->>> typat 1 1 2 2 2 2
->>> xred
->>> 0 0 0
->>> 0 0 0.5
->>> 0.25 0.25 0.125
->>> 0.25 0.25 0.625
->>> 0.75 0.75 0.375
->>> 0.75 0.75 0.875
->>> acell
->>> 1.0 1.0 1.0 angstrom
->>> rprim
->>> 0 2.785 2.745
->>> 2.785 0 2.745
->>> 5.57 5.57 0
->>>
->>> ABINIT then thinks I have P1 (non)symmetry. However, a tool such as
->>> FINDSYM at
->>> http://stokes.byu.edu/cgi-bin/iso/findsym.cgi readily verifies that I
->>> still in
->>> fact have I4/mmm symmetry. What could be wrong?
->>>
->>> Thanks--
->>> Bryce
->>>
->>
->>
->>
->> --
->> Quan Phung Manh
->> Khoa Hoá học - ĐH Khoa học tự nhiên - 19 Lê Thánh Tông Hà Nội
->>
->>
->


-- 

Prof. Aldo Humberto Romero
CINVESTAV-Unidad Queretaro
Libramiento Norponiente 2000
CP 76230, Queretaro, QRO, Mexico
tel: 442 211 9909
fax: 442 211 9938

email: aromero@qro.cinvestav.mx
        aldorome@gmail.com
www: qro.cinvestav.mx/~aromero