||
关注:
1) k点和q点的物理意义;
2) k点和q点在倒空间的取样方法;
3) 电声耦合作用计算时,k点和q点的取点要求
1.nq,xq的区别
nq属于放入这个&INPUTPH字段中的参数
xq(1) xq(2) xq(3) | REAL |
---|---|
The phonon wavevector, in units of 2pi/a0 (a0 = lattice parameter). Not used if ldisp=.true. |
|
|
ldisp | LOGICAL |
---|---|
Default: | .false. |
If .true. the run calculates phonons for a grid of q-points specified by nq1, nq2, nq3 - for direct calculation of the entire phonon dispersion. |
事例:
(1)
phonon of a225 at Gamma
&inputph
tr2_ph=1.0d-12,
prefix='a225',
amass(1)=1.008
amass(2)=44.955910,
trans=.true.,
ldisp=.true.,
outdir='/home/xiaoqiugood/pwscf/pw/tmp/tmp3',
fildyn='a225.dyn',
nq1=4,nq2=4,nq3=4
/
(2)
cat > phdos.in <<EOF
&input
asr='simple',
dos=.true.,
amass(1)=1.008,
amass(2)=44.955910,
flfrc='a225.fc',
nk1=20,nk2=10,nk3=10,
deltaE=1.0,
fldos='a225.dos'
/
EOF
$PW_ROOT/matdyn.x < phdos.in > phdos.out
(3)
cat > q2r.in << EOF
&input
fildyn='a225.dyn', zasr='simple', flfrc='a225.fc'
/
EOF
$PW_ROOT/q2r.x < q2r.in > q2r.out
cat > matdyn.in << EOF
&input
asr='simple', amass(1)=1.008, amass(2)=44.955910
flfrc='a225.fc', flfrq='a225.freq'
/
151
-1.000000 0.5000000 0.0000000E+00 1
-0.9833333 0.5000000 1.6666669E-02 2
-0.9666667 0.5000000 3.3333331E-02 3
-0.9500000 0.5000000 5.0000001E-02 4
....
-0.7500000 0.7500000 0.0000000E+00 151
EOF
$PW_ROOT/matdyn.x < matdyn.in > matdyn.out
(4)
ic=6
qpoints="0.500000000000000E+00,-0.500000000000000E+00,0.100000000000000E+01\
-0.250000000000000E+00,-0.125000000000000E+01,0.250000000000000E+00\
-0.500000000000000E+00,-0.500000000000000E+00,0.000000000000000E+00\
0.000000000000000E+00,-0.100000000000000E+01,0.500000000000000E+00\
0.500000000000000E+00,-0.500000000000000E+00,-0.500000000000000E+00"
for qpoint in $qpoints ; do
ic=`expr $ic + 1`
qx=`echo $qpoint | cut -d, -f1`
qy=`echo $qpoint | cut -d, -f2`
qz=`echo $qpoint | cut -d, -f3`
cat >$name.ph$ic.in << EOF
phonon of $name at Gamma
&inputph
tr2_ph=1.0d-12,
prefix='$name',
amass(1)=1.008
amass(2)=44.955910,
outdir='$TMP_DIR',
fildyn='$name.dyn$ic',
/
$qx $qy $qz
EOF
$PARA_PREFIX $PW_ROOT/ph.x < $name.ph$ic.in > $name.ph$ic.out
done
2. 对称性问题
|
Archiver|手机版|科学网 ( 京ICP备07017567号-12 )
GMT+8, 2024-9-27 07:33
Powered by ScienceNet.cn
Copyright © 2007- 中国科学报社