ABINIT Discussion Forums

Dear all
I calculated CuBO2 when I used space group number 166 see below
##Definition of the unit cell
acell 2*2.84 16.52 angstrom
brvltt -1
spgroup 166
rprim 0.86602540378 0.5 0.0
-0.86602540378 0.5 0.0
0.0 0.0 1.0

And I got output files still rhombohedral phase but no cell parameter
I used crystallographic server to generated atomic position
What happen about my problem ? see below

Symmetries : space group R-3 m (#166); Bravais hR (rhombohedral)
================================================================================
Values of the parameters that define the memory need of the present run
intxc = 0 ionmov = 2 iscf = 17 xclevel = 2
lmnmax = 12 lnmax = 4 mband = 41 mffmem = 1
P mgfft = 60 mkmem = 72 mpssoang= 3 mpw = 2228
mqgrid = 3001 natom = 12 nfft = 216000 nkpt = 144
nloalg = 4 nspden = 1 nspinor = 1 nsppol = 1
nsym = 12 n1xccc = 1 ntypat = 3 occopt = 1
PAW method is used; the additional fine FFT grid is defined by:
mgfftf= 72 nfftf = 373248
================================================================================
P This job should need less than 456.054 Mbytes of memory.
Rough estimation (10% accuracy) of disk space for files :
WF disk file : 200.718 Mbytes ; DEN or POT disk file : 2.850 Mbytes.
================================================================================

-outvars: echo values of preprocessed input variables --------
acell 1.0000000000E+00 1.0000000000E+00 1.0000000000E+00 bohr
amu 6.35460000E+01 1.08110000E+01 1.59994000E+01
dilatmx 1.20000000E+00
ecut 2.20000000E+01 Hartree
ecutsm 5.00000000E-01 Hartree
ionmov 2
ixc 11

Best regards
Abdulmutta

In some cases, like this one, abinit computes and represents the primitive cell by setting acell = 1.0 1.0 1.0 all cell lengths inside rprim. Remember that the true cell axes, rprimd, are a combination of acell and rprim, so that it doesn't really matter whether acell has the lengths or they are buried in rprim. This is a case where they are all in rprim. I think your calculation is fine, at least as far as this issue is concerned.

Dear sir
After that rprim as input files was
rprim 0.86602540378 0.5 0.0
-0.86602540378 0.5 0.0
0.0 0.0 1.0

when I computes in abinit as output files generated rprim was
rprim 2.6834111087E+00 1.5492681260E+00 1.0406091905E+01
-2.6834111087E+00 1.5492681260E+00 1.0406091905E+01
0.0000000000E+00 -3.0985362519E+00 1.0406091905E+01

In column * R1p(i)=scalecart(i)rprim(i,1)*acell(1)
* R2p(i)=scalecart(i)rprim(i,2)*acell(2)
* R3p(i)=scalecart(i)rprim(i,3)*acell(3)
In first column, that right
second column, that incorrect as R(3,3)
third column, that incorrect as all

I got as output file, it doesn't correct, right
What happened my problem ?

Best regards
Abdulmutta

Hi,
I think your input rprim is not right. Try it again using the same input acell, spgroup, and brvltt, but instead of giving rprim explicitly, input angdeg 90 90 120 instead and see what happens.

Dear sir
After your introduced, I found that it is shown the same rprim see below
rprim 2.6834111087E+00 1.5492681260E+00 1.0406091905E+01
-2.6834111087E+00 1.5492681260E+00 1.0406091905E+01
0.0000000000E+00 -3.0985362519E+00 1.0406091905E+01

This is my input files
##Definition of the unit cell
acell 2*2.84 16.52 angstrom
brvltt -1
spgroup 166
angdeg 90 90 120

Please help me, I tries this problem 2 week ago

Best regards
Abdulmutta