Error message with Wurtzite GaN

Posted on : December 20, 2005 (Tue) 02:44:58

by Sebastien Beysserie

Hi,
I consistently get an error message "wrn in spmain...etop

#################### Wurtzite GaN #####################
# calctyp file
go GaN
#
# brvtyp a c/a b/a alpha beta gamma
hex 3.189 1.62 1.00 90 90 120
#
# edelt ewidth reltyp sdftyp magtyp
0.001 2.0 nrlls mjw nmag
#
# record outtyp bzqlty maxiter pmix
init update t 200 0.0
#
# ntyp
2
# type ncmp rmt field lmx anclr conc
Ga 1 0 0 2 31 100
N 1 0 0 2 7 100
# natm
4
0.0 0.0 0.0 Ga
0.3333 0.6666 0.5 Ga
0.0 0.0 0.375 N
0.3333 0.6666 0.875 N
############################# end #######################


The program stops the iterative process with the following message:


#########################################################
***** self-consistent iteration starts *****
Ga_2N_2
itr= 1 neu=-50.9942 moment= 0.0000 te= -7522.4303877 err=
0.165
itr= 2 neu=-50.9931 moment= 0.0000 te= -7522.4293597 err=
0.165
itr= 3 neu=-50.9909 moment= 0.0000 te= -7522.4228068 err=
0.165
itr= 4 neu=-50.9787 moment= 0.0000 te= -7522.2751124 err=
0.165
itr= 5 neu=-50.7460 moment= 0.0000 te= -7522.1561682 err=
0.165
itr= 6 neu=-50.7098 moment= 0.0000 te= -7521.2756276 err=
0.163
itr= 7 neu=-50.4977 moment= 0.0000 te= -7521.8970934 err=
0.164
itr= 8 neu=-50.4941 moment= 0.0000 te= -7521.8992191 err=
0.164
itr= 9 neu=-50.4897 moment= 0.0000 te= -7521.8837177 err=
0.164
itr= 10 neu=-50.2537 moment= 0.0000 te= -7521.5728899 err=
0.163
***wrn in spmain...etop interval= 11 cpu time= 5.00 sec
sdftyp=mjw reltyp=nrlls dmpc=0.000
Ga_2N_2
itr= 11 neu-50.2537 chr,spn 1.8580 0.0000 intc,ints 52.1083
0.0000
rms err= 0.163 -0.008 0.163 -0.008
ef= 0.9127267 0.9127267 def= 1.1172784 1.1172784
total energy= -7521.5728899
#########################################################

Is there any way to avoid this error message or is there an error in my input file?
Any help is greatly appreciated, thank you.
Sebastien

Re:Error message with Wurtzite GaN

Posted on : December 20, 2005 (Tue) 21:01:49

by fecher

The message tells you that the Fermi energy is above the energy window.
You should restart the calculation with record = 2nd (not init), then the energy window should be recalculated from the values found in the potential file, sometimes one has to do several restarts.

However, your input file seems to be a little buggy.
You give a in Angstrom and not in atomic units as required !
The mixing coefficient is set to 0.00 !

To use the integration quality test is fast but very optimistic.
I also use a different setup of the atoms in the Wurzit structure, I did not check whether yours is ok.

The following input should work:

#################### Wurtzite GaN #####################
# calctyp file
go GaN
#
# brvtyp a c/a b/a alpha beta gamma
hcp 6.03 1.626 1.00 90 90 120
#
# edelt ewidth reltyp sdftyp magtyp
0.001 2.5 nrlls mjw nmag
#
# record outtyp bzqlty maxiter pmix
init update m 200 0.02
#
# ntyp
2
# type ncmp rmt field lmx anclr conc
Ga 1 0 0 2 31 100
N 1 0 0 2 7 100
# natm
4
0.66667 0.33333 0.000 Ga
0.33333 0.66667 0.500 Ga
0.66667 0.33333 0.375 N
0.33333 0.66667 0.875 N
############################# end #######################

Have fun, Ciao
Gerhard

>Hi,
>I consistently get an error message "wrn in spmain...etop>
>
>#################### Wurtzite GaN #####################
># calctyp file
> go GaN
>#
># brvtyp a c/a b/a alpha beta gamma
> hex 3.189 1.62 1.00 90 90 120
>#
># edelt ewidth reltyp sdftyp magtyp
> 0.001 2.0 nrlls mjw nmag
>#
># record outtyp bzqlty maxiter pmix
> init update t 200 0.0
>#
># ntyp
> 2
># type ncmp rmt field lmx anclr conc
> Ga 1 0 0 2 31 100
> N 1 0 0 2 7 100
># natm
>4
>0.0 0.0 0.0 Ga
>0.3333 0.6666 0.5 Ga
>0.0 0.0 0.375 N
>0.3333 0.6666 0.875 N
>############################# end #######################
>
>
>The program stops the iterative process with the following message:
>
>
>#########################################################
> ***** self-consistent iteration starts *****
> Ga_2N_2
> itr= 1 neu=-50.9942 moment= 0.0000 te= -7522.4303877 err=
>0.165
> itr= 2 neu=-50.9931 moment= 0.0000 te= -7522.4293597 err=
>0.165
> itr= 3 neu=-50.9909 moment= 0.0000 te= -7522.4228068 err=
>0.165
> itr= 4 neu=-50.9787 moment= 0.0000 te= -7522.2751124 err=
>0.165
> itr= 5 neu=-50.7460 moment= 0.0000 te= -7522.1561682 err=
>0.165
> itr= 6 neu=-50.7098 moment= 0.0000 te= -7521.2756276 err=
>0.163
> itr= 7 neu=-50.4977 moment= 0.0000 te= -7521.8970934 err=
>0.164
> itr= 8 neu=-50.4941 moment= 0.0000 te= -7521.8992191 err=
>0.164
> itr= 9 neu=-50.4897 moment= 0.0000 te= -7521.8837177 err=
>0.164
> itr= 10 neu=-50.2537 moment= 0.0000 te= -7521.5728899 err=
>0.163
> ***wrn in spmain...etop> interval= 11 cpu time= 5.00 sec
> sdftyp=mjw reltyp=nrlls dmpc=0.000
> Ga_2N_2
> itr= 11 neu-50.2537 chr,spn 1.8580 0.0000 intc,ints 52.1083
>0.0000
> rms err= 0.163 -0.008 0.163 -0.008
> ef= 0.9127267 0.9127267 def= 1.1172784 1.1172784
> total energy= -7521.5728899
>#########################################################
>
>Is there any way to avoid this error message or is there an error in my input file?
>Any help is greatly appreciated, thank you.
>Sebastien