Dear Punit
problems computing cholesky
The first source of such error is generally in the structure itself.
If you try to reach the ground state of an unphysical structure the
diagonalization may be affected by strong instabilities. I'm not 100%
sure that this is your case: the structure is strange, but after all
I've no experience of La2O3. However, at first sight (I opened your
input file with xcrysden) there are two inequivalent O sites in your
structure. A fourfold-coordinated O which forms three short (2.32 A)
La-O bonds and one longer (2.54 A). This is apparently reasonable.
There is a different sixfold-(barely)coordinated O site, almost an
interstitial O atom in an octahedral La cage, having longer La-O
distances (2.75 A). O in oxides has generally no chemical tendency to
stay in such an interstitial position, and this is likely the source
of your scf instability. Hence I recommend that you double-check the
structure. As a minor point, the vacuum space between periodically
replicated images along the z axis is a bit on the side of "scarce".
You should at least double the space occupied by your system
(including the main part of the tail of charge density). You might
also want to use a special solver to decouple the electrostatic
potential along the z axis (see for example assume_isolated='esm' in
the vacuum-slab-vacuum geometry).
HTH
Giuseppe
Quoting Punit Kumar <[email protected]>:
Hello QE users
Recently I have started working on QE. Currently I am trying to relax La2O3
slab which is 4 layers deep. But while doing the calculation I have
encountered an error which is "Problem computing cholesky". I have searched
this issue on QE mailing list and found that to remove this problem one has
to use norm-conserving PP. I am also using norm-conserving PP but error
still remains the same. Since I am new user I have no clue how to tackle
this problem. Any help to resolve this error is highly appreciated. Below I
have given the crash report and my input file
*CRASH*
task # 0
from cdiaghg : error # 151
problems computing cholesky
*Input file*
&CONTROL
title = 'lao' ,
prefix = 'lao'
calculation = 'relax' ,
restart_mode = 'from_scratch'
outdir = './out' ,
pseudo_dir =
'/home/punit/Documents/punit/sg15_oncv_upf_2015-10-07/' ,
/
&SYSTEM
ibrav = 0,
celldm(1)= 1.89 ,
nat = 20,
ntyp = 2,
ecutwfc = 50 ,
ecutrho = 500 ,
occupations = 'smearing' ,
smearing = 'gaussian' ,
degauss = 0.020
/
&ELECTRONS
electron_maxstep = 500 ,
conv_thr = 1.0d-5 ,
mixing_mode = 'plain' ,
mixing_beta = 0.7 ,
diagonalization = 'david' ,
/
&IONS
/
&CELL
/
CELL_PARAMETERS alat
3.843000000 0.000000000 0.000000000
-1.921500000 3.328100000 0.000000000
0.000000000 -0.000000000 48.262800000
ATOMIC_SPECIES
La 138.90 La_ONCV_PBE-1.0.upf
O 15.999 O_ONCV_PBE-1.0.upf
ATOMIC_POSITIONS alat
La 0.00000000 2.21880000 13.62680000 1 1 1
La 1.92150000 1.10940000 16.84560000 1 1 1
O 0.00000000 0.00000000 12.00000000 1 1 1
O 0.00000000 2.21880000 16.16450000 1 1 1
O 1.92150000 1.10940000 14.30790000 1 1 1
La 0.00000000 2.21880000 20.09920000 1 1 1
La 1.92150000 1.10940000 23.31800000 1 1 1
O 0.00000000 0.00000000 18.47240000 1 1 1
O 0.00000000 2.21880000 22.63690000 1 1 1
O 1.92150000 1.10940000 20.78030000 1 1 1
La 0.00000000 2.21880000 26.57160000 1 1 1
La 1.92150000 1.10940000 29.79040000 1 1 1
O 0.00000000 0.00000000 24.94480000 1 1 1
O 0.00000000 2.21880000 29.10930000 1 1 1
O 1.92150000 1.10940000 27.25270000 1 1 1
La 0.00000000 2.21880000 33.04400000 0 0 0
La 1.92150000 1.10940000 36.26280000 0 0 0
O 0.00000000 0.00000000 31.41720000 0 0 0
O 0.00000000 2.21880000 35.58170000 0 0 0
O 1.92150000 1.10940000 33.72510000 0 0 0
K_POINTS automatic
4 4 1 0 0 0
Regards
Punit (PhD)
IIT Bombay
GIUSEPPE MATTIOLI
CNR - ISTITUTO DI STRUTTURA DELLA MATERIA
Via Salaria Km 29,300 - C.P. 10
I-00015 - Monterotondo Scalo (RM)
Mob (*preferred*) +39 373 7305625
Tel + 39 06 90672342 - Fax +39 06 90672316
E-mail: <[email protected]>
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