Coordinate system setting in rndstr.in

Alloy Theoretic Automated Toolkit (ATAT)
1

Dear prof. A.van de Walle,
I am using mcsqs code in ATAT to generate a special quasi-randomness cell with a coordinate system , x=1 0 0 y=0 1 1 c= 0 -1 1 in fcc crystallographic orientation, i.e. the unit cell with [1 0 0], [0 1 1],[0 -1 1] crystallographic orientation, and have been reading your paper(10.1016/j.calphad.2013.06.006), where you said that the first line in rndstr.in denoting the coordinate system can be substitued by a 3*3 matrix, so I taken the following matrix as the coordinate system to run corrdump code, the rndstr.in as follows
3.5 0 0
0 -3.5 3.5
0 3.5 3.5
.0 .5 .5
.5 .0 .5
.5 .5 .0
.0 .0 .0 Ni=.333333,Fe=.333333,Co=.333334
corrdump -l=rndstr.in -ro -noe -nop -clus -2=3.9
wherein 3.5 is the lattice constant. However an error happened, that is segmentation fault.

Did I miss something or misunderstand your paper? or whether should I keep the coordinate system or unit cell with ‘3.5 3.5 3.5 90 90 90’ and take a rotation of the unit cell respect to ‘1 0 0-axis’ with 45M-BM-0 through multiplication of rotation matrix and lattice vector matrix '.0 .5 .5, .5 .0 .5, .5 .5 .0 ’ ?

Would you please help me fix the issue or give an example with a 3*3 matrix as being the coordinate system?

Thanks in advance!
Wei

2

  1. when I run the command you give with the file you give, I get no error message. So there maybe some invisible characters in your input file that confuse the code (so paste the numbers from your post in a fresh new empty text file). Or you should get the latest version of ATAT.

  2. You input file seems to want to defines a tetragonal (1st 3 lines) face centered (next 3 lines) crystal system. While this is mathematically valid, there is no tetragonal face centered bravais lattice, so I suspect this is not what you want. If it helps (i) rotating a lattice by 45 degree is unnecessary does not change the results (ii) your "rotation" actually enlarges two of the vectors by sqrt(2).

  3. you can check if this is the structure you want by running nnshell -l=rndstr.in (to see neighbors) or cellcvrt -pbv < rndstr.in to see lattice type.

3

Thank you very much, Prof. A.van de Walle.
Yes, that’s some character errors produced the fault. I can run through the script at any version of mcsqs code.

Sincerely
Wei