[Wien] problem with supercell

[Yaron and Angelica]

Hello Stefaan,

Friday, July 18, 2003, 5:39:07 PM, you wrote:

>> SC> Can you construct a unit cell for the small, regular cell?
>>     Yes, I constructed a unit cell - 2 inequivalent atoms, space group
>>     Pm-3m and there was 48 symmetry operations.
>>     After that in a new session I took 16 atoms Fe1,...Fe8, Al1,...Al8;
>>     And the same space group P m-3m.

SC> That's probably where it goes wrong. Make a P-structfile (without giving
SC> space group information), and put all Fe atoms and all Al atoms at the same
SC> inequivalent position (you just have 2 inequivalent positions then). Then,
SC> before doing anything else, remove the atom at the place where you want the
SC> vacancy. Then initialize, and accept the new structures produced by nn
SC> and/or sgroup. Most likely you will have much less than 15 or 16 ineq. pos.

SC> Because you added a number after each atom name (Fe3, Al5,...), the program
SC> is forced to consider each of them as an inequivalent atom.
I followed your instructions and created a cell. But after initialization
I got this output:

Commandline: x nn
Program input is: "2 " 

  please specify nn-bondlength factor: (usually=2)

    ATOM 1  Fe         ATOM12  Al        
 RMT( 1)=1.70000 AND RMT(12)=1.80000
 SUMS TO 3.50000  LT.  NN-DIST= 5.49194

    ATOM 2  Fe         ATOM10  Al        
 RMT( 2)=1.70000 AND RMT(10)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM 3  Fe         ATOM12  Al        
 RMT( 3)=1.70000 AND RMT(12)=1.80000
 SUMS TO 3.50000  LT.  NN-DIST= 5.49194

    ATOM 4  Fe         ATOM12  Al        
 RMT( 4)=1.70000 AND RMT(12)=1.80000
 SUMS TO 3.50000  LT.  NN-DIST= 5.49194

    ATOM 5  Fe         ATOM 9  Al        
 RMT( 5)=1.70000 AND RMT( 9)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM 6  Fe         ATOM11  Al        
 RMT( 6)=2.00000 AND RMT(11)=1.70000
 SUMS TO 3.70000  LT.  NN-DIST= 5.49194

    ATOM 7  Fe         ATOM15  Al        
 RMT( 7)=1.70000 AND RMT(15)=1.80000
 SUMS TO 3.50000  LT.  NN-DIST= 6.72623

    ATOM 8  Al         ATOM11  Al        
 RMT( 8)=1.70000 AND RMT(11)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 3.88339

    ATOM 9  Al         ATOM 4  Fe        
 RMT( 9)=1.70000 AND RMT( 4)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM10  Al         ATOM 1  Fe        
 RMT(10)=1.70000 AND RMT( 1)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM11  Al         ATOM 8  Al        
 RMT(11)=1.70000 AND RMT( 8)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 3.88339

    ATOM12  Al         ATOM15  Al        
 RMT(12)=1.80000 AND RMT(15)=1.80000
 SUMS TO 3.60000  LT.  NN-DIST= 3.88339

    ATOM13  Al         ATOM 4  Fe        
 RMT(13)=1.70000 AND RMT( 4)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM14  Al         ATOM 3  Fe        
 RMT(14)=1.70000 AND RMT( 3)=1.70000
 SUMS TO 3.40000  LT.  NN-DIST= 6.72623

    ATOM15  Al         ATOM12  Al        
 RMT(15)=1.80000 AND RMT(12)=1.80000
 SUMS TO 3.60000  LT.  NN-DIST= 3.88339
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
 ERROR: Mult not equal. PLEASE CHECK outputnn-file
 ERROR: ityp not equal. PLEASE CHECK outputnn-file
STOP: NN created a new CASE.STRUCT_NN FILE
0.0u 0.0s 0:00 0% 0+0k 0+0io 0pf+0w

What is wrong now... please take your time.
 

Best regards,
Angelica                            mailto:strutza at bgumail.bgu.ac.il