Mc swaps on only one sublattice

[cmt_atat]

Hi,

Consider the example lat.in system described in the mmaps -h output:

A lattice for the Li_x Co_y Al_(1-y) O_2 system:
0.707 0.707 6.928 90 90 120
0.3333 0.6667 0.3333
-0.6667 -0.3333 0.3333
0.3333 -0.3333 0.3333
0 0 0 Li,Vac
0.3333 0.6667 0.0833 O
0.6667 0.3333 0.1667 Co,Al
0 0 0.25 O

Armed with a suitable cluster expansion, perform a canonical simulation using memc2 (with an appropriate initial structure and conccons.in file) to generate a representative structure at T=1000 K with x=1.0 (i.e fully lithiated) and some desired y value.

Starting with the fully lithiated 1000 K structure, manually replace half the Li with Vac(ancies), and use this as the initial structure for a new canonical simlation at some relatively low temperature, e.g. 300 K.

Question: Is it possible to swap only Li and Vac, leaving Co and Al atoms unperturbed?

Thanks,
Craig

[avdw]

To freeze one sublattice, you can create a file called frozensite.in that contains a list of the sites you want to freeze (one number per site, indicating its line number, starting at 0). One caution: the sites are internally re-ordered for efficiency - to get the right order type:

cellcvrt.exe -abc < lat.in

In your case, this outputs:

0.707000 0.707000 6.928000 90.000000 90.000000 120.000000
0.333300 0.666700 0.333300
-0.666700 -0.333300 0.333300
0.333300 -0.333300 0.333300
0.000000 0.000000 0.000000 Li,Vac
0.666700 0.333300 0.166700 Co,Al
0.333300 0.666700 0.083300 O
0.000000 -0.000000 0.250000 O

So your frozensite.in would contain:

1