Dear Yeonsig,

It is pretty easy to do that with the "Charge Density Scripts" from the Jónsson group

http://theory.cm.utexas.edu/vtsttools/scripts.html

Best regards

I think the script in the above link only gives

chgavg,sum,diff,paravg and so on.

It doesn't split the CHGCAR/PARCHG into each spin components.

Rather it requires two CHGCAR files to calculate their sum, diff, avg.

I'm focusing on splitting of PARCHG/CHGCAR file.

You have to download the scripts, there are two scripts called chgsplit, check that.

@ Sinhué López

I really appreciate your help.

I downloaded the scripts (chgsplit.sh & chgsplit.pl), then executed.

(by using command ./chgsplit.sh CHGCAR)

However, the CHGCAR is not appropriately splitted as I expected.

So I checked the code like the following:

---------------------------------------------------------------------------------------------------------------------

#!/bin/bash

# AA 06-06-2008

file=$1

echo " Input file :: \"$file\" "

# Get the total number of atoms

set -- $( sed '7q;d' $file )

sum=0

while [ $# -gt 0 ]; do

i=$1

sum=$( echo "$sum + $i" | bc )

shift

done

# Cut out the header info

nh=$((10+sum))

rm -f haus

sed "$nh"q $file > haus

# Find the FFT grid line and use it to split the file

set -- $( grep -n "$( head -$nh $file | tail -1 )" $file | \

sed 's/:/ /' | awk '{print $1}' )

l1=$1 ; l2=$2 # line numbers for the FFT grid info line

l3=$( wc -l $file | awk '{print $1}' )

# Split, and paste the header on top again

rm -f cf1 cf2

cp haus cf1

cp haus cf2

echo " Total spin (file \"cf1\") "

sed -n "$((l1+1)),$((l2-1)) p" $file >> cf1

# head -$((l2-1)) $file | tail -n +$((l1+1)) >> cf1

echo " Magnetization (file \"cf2\") "

sed -n "$((l2+1)),$ p" $file >> cf2

# tail -$((l3-l2)) $file >> cf2

rm -f haus

----------------------------------------------------------------------------------------------------------------------

I'm checking the all the variables, but what is the "$2" and "$l2"?

The website doesn't have any description on chgsplit.sh & chgsplit.pl

"$2" seems to be declared by the command .

could you tell me what those variables are??

Thanks.

Ok, not your fault I guess you miss a bit of bash basic knowledge. $1 and $2 are the file passed by the command. line . So the actual command should be ./run.sh $1 $2

Dear Federico Brivio, so we have to execute:

./chgsplit.sh CHGCAR $1 $2, then I am getting

Input file :: "CHGCAR"

Total spin (file "cf1")

Magnetization (file "cf2")

What does these file contain??

Continued to Sinhué López 's answer. If you want to split spin up and spin down of the PARCHG/CHGCAR, you could do the following: (using the VTST scripts https://theory.cm.utexas.edu/vtsttools/scripts.html)

1) chgsplit.sh PARCHG/CHGCAR

This will generate two files cf1 and cf2. cf1 is the total spin (up+down). cf2 is the magnetization (up - down)

2) use VESTA to add up cf1 and cf2, and visualize it, this gives up spin up.

3) chgdiff.pl cf1 cf2

This gives you (up+down)-(up-down) = 2*down. The output file is

CHGCAR_diff . Use VESTA to visualize it. This gives you spin down. Or simply use VESTA to substrate cf1 from cf2 and you will get spin down.