FCC and BCC non primitive unit cell

Total energy, geometry optimization, DFT+U, spin....

Moderator: bguster

Locked
Hola
Posts: 9
Joined: Thu Mar 29, 2018 10:51 am

FCC and BCC non primitive unit cell

Post by Hola » Wed Jan 30, 2019 5:13 pm

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.

ebousquet
Posts: 469
Joined: Tue Apr 19, 2011 11:13 am
Location: University of Liege, Belgium

Re: FCC and BCC non primitive unit cell

Post by ebousquet » Fri Feb 01, 2019 6:00 pm

Hello Hola,
Which atoms (and spins if so) did you put on each xred?
Best wishes,
Eric

Locked