#!/bin/sh

###############################################################################
##
##  GCSCF EXAMPLE
##
###############################################################################

EXAMPLE_DIR=`pwd`

# check whether echo has the -e option
if test "`echo -e`" = "-e" ; then ECHO=echo ; else ECHO="echo -e" ; fi

$ECHO
$ECHO "run_example_GCSCF : starting"
$ECHO
$ECHO "This example shows how to use Grand Canonical SCF (GCSCF) in NEB."
$ECHO

# set the needed environment variables
. ../../../environment_variables

# required executables and pseudopotentials
BIN_LIST="neb.x"
PSEUDO_LIST="Al.pbe-n-van.UPF H.pbe-van_ak.UPF"

$ECHO
$ECHO "  executables directory: $BIN_DIR"
$ECHO "  pseudo directory:      $PSEUDO_DIR"
$ECHO "  temporary directory:   $TMP_DIR"
$ECHO "  checking that needed directories and files exist...\c"

# check for directories
for DIR in "$BIN_DIR" "$PSEUDO_DIR" ; do
    if test ! -d $DIR ; then
        $ECHO
        $ECHO "ERROR: $DIR not existent or not a directory"
        $ECHO "Aborting"
        exit 1
    fi
done
for DIR in "$TMP_DIR" "$EXAMPLE_DIR/results" ; do
    if test ! -d $DIR ; then
        mkdir $DIR
    fi
done
cd $EXAMPLE_DIR/results

# check for executables
for FILE in $BIN_LIST ; do
    if test ! -x $BIN_DIR/$FILE ; then
        $ECHO
        $ECHO "ERROR: $BIN_DIR/$FILE not existent or not executable"
        $ECHO "Aborting"
        exit 1
    fi
done

# check for pseudopotentials
for FILE in $PSEUDO_LIST ; do
    if test ! -r $PSEUDO_DIR/$FILE ; then
       $ECHO
       $ECHO "Downloading $FILE to $PSEUDO_DIR...\c"
       echo $WGET $PSEUDO_DIR/$FILE $NETWORK_PSEUDO/$FILE
            $WGET $PSEUDO_DIR/$FILE $NETWORK_PSEUDO/$FILE 2> /dev/null
    fi
    if test $? != 0; then
        $ECHO
        $ECHO "ERROR: $PSEUDO_DIR/$FILE not existent or not readable"
        $ECHO "Aborting"
        exit 1
    fi
done
$ECHO " done"

# how to run executables
PW_COMMAND="$PARA_PREFIX $BIN_DIR/pw.x $PARA_POSTFIX"
NEB_COMMAND="$PARA_PREFIX $BIN_DIR/neb.x $PARA_POSTFIX"
$ECHO
$ECHO "  running Born-Oppenheimer NEB as: $NEB_COMMAND"
$ECHO

# NEB calculation for Al001+H with bc3 (vacuum-slab-metal),
# target mu = -5.00V
cat > Al001+H_GCSCF_vm05.in << EOF
BEGIN
BEGIN_PATH_INPUT
&PATH
  restart_mode  = 'from_scratch',
  string_method = 'neb',
  nstep_path    = 50,
  opt_scheme    = 'broyden',
  num_of_images = 5,
/
END_PATH_INPUT
BEGIN_ENGINE_INPUT
&CONTROL
  prefix        = 'Al001+H_GCSCF_vm05'
  outdir        = '$TMP_DIR/',
  pseudo_dir    = '$PSEUDO_DIR/',
/
&SYSTEM
  ibrav         = 0,
  nat           = 5,
  ntyp          = 2,
  ecutwfc       = 20.0,
  occupations   = 'smearing',
  nosym         = .TRUE.
  smearing      = 'mv',
  degauss       = 0.02,
  assume_isolated='esm',
  esm_bc        = 'bc3',
  lgcscf        = .TRUE.
  gcscf_mu      = -5.00
/
&ELECTRONS
  mixing_beta = 0.1,
/
ATOMIC_SPECIES
  Al  26.981538   Al.pbe-n-van.UPF
  H    1.00794    H.pbe-van_ak.UPF
BEGIN_POSITIONS
FIRST_IMAGE
ATOMIC_POSITIONS bohr
Al  0.00000000   0.00000000   0.00000000 0 0 0
Al  5.41113843   0.00000000   0.00000000 0 0 0
Al  0.00000000   5.41113843   0.00000000 0 0 0
Al  5.41113843   5.41113843   0.00000000 0 0 0
H   0.00000000   0.00000000   3.11055367 0 0 1
LAST_IMAGE
ATOMIC_POSITIONS bohr
Al  0.00000000   0.00000000   0.00000000 0 0 0
Al  5.41113843   0.00000000   0.00000000 0 0 0
Al  0.00000000   5.41113843   0.00000000 0 0 0
Al  5.41113843   5.41113843   0.00000000 0 0 0
H   5.41113843   5.41113843   3.11055367 0 0 1
END_POSITIONS
K_POINTS automatic
6 6 1 1 1 0
CELL_PARAMETERS bohr
 10.82227686   0.00000000   0.00000000
  0.00000000  10.82227686   0.00000000
  0.00000000   0.00000000  22.67672253
END_ENGINE_INPUT
END
EOF
$ECHO "  running NEB calculation for Al001+H with ESM+constant-mu"
$ECHO "  (target mu = -0.5V vs pzc)...\c"
$NEB_COMMAND -inp Al001+H_GCSCF_vm05.in > Al001+H_GCSCF_vm05.out
check_failure $?
$ECHO " done"
# clean current dir & $TMP_DIR
$ECHO "  cleaning ./ & $TMP_DIR...\c"
rm -rf neb.dat pw_1.in pw_2.in out.1_0 out.2_0
rm -rf $TMP_DIR/Al001+H_GCSCF_vm05.*
rm -rf $TMP_DIR/Al001+H_GCSCF_vm05_*/Al001+H_GCSCF_vm05.save
rm -rf $TMP_DIR/Al001+H_GCSCF_vm05_*/Al001+H_GCSCF_vm05.update
rm -rf $TMP_DIR/Al001+H_GCSCF_vm05_*/Al001+H_GCSCF_vm05.wfc*
#rm -rf $TMP_DIR/Al001+H_GCSCF_vm05_*/PW.out
mv $TMP_DIR/Al001+H_GCSCF_vm05_* .
$ECHO " done"

$ECHO
$ECHO "run_example_GCSCF: done"
