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FCC and BCC non primitive unit cell

Posted: Wed Jan 30, 2019 5:13 pm
by Hola
Hi everyone,

I want to define a FCC (and BCC) structure in my input file using a non primitive
unit cell with
rprim
1 0 0
0 1 0
0 0 1

For the FCC structure I used 4 atoms with xred :
xred
0.0 0.0 0.0
0.5 0.0 0.5
0.5 0.5 0.0
0.0 0.5 0.5

For the BCC structure I defined two atoms with
xred
0.0 0.0 0.0
0.5 0.5 0.5

I launch the calculation. And in my log file it's written for both structure :
"symlatt : the Bravais lattice is cP (primitive cubic)"

In my inputfile I defined a FCC (and BCC) structure and I don't understand why in my log file the code reconizes a primitive cubic cell.

How can I define a FCC and BCC structure with non primitive vectors ?

Best regards.

Re: FCC and BCC non primitive unit cell

Posted: Fri Feb 01, 2019 6:00 pm
by ebousquet
Hello Hola,
Which atoms (and spins if so) did you put on each xred?
Best wishes,
Eric