Dear all
I'm doing phonon calculation at Gamma point (q) in order to estimate the
reaction rate constants for a micro-kinetic model. I have perturbed only the
adsorbate molecule with the 3 surface atoms, connected to adsorbate, using
"nat-todo" option. However, i got 15 negative frequencies (should be 6 as i
know ) ,with high absolute value.
Can you please help me to know what is wrong with my input files ?
Below are the output & input files:
Mode symmetry, C_1 (1) point group:
freq ( 1 - 1) = -2762.6 [cm-1] --> A I+R freq
( 2 - 2) = -2570.3 [cm-1] --> A I+R freq ( 3 - 3)
= -2460.4 [cm-1] --> A I+R freq ( 4 - 4) =
-2423.6 [cm-1] --> A I+R freq ( 5 - 5) = -2356.3
[cm-1] --> A I+R freq ( 6 - 6) = -2158.0 [cm-1]
--> A I+R freq ( 7 - 7) = -2151.1 [cm-1] --> A
I+R freq ( 8 - 8) = -2067.5 [cm-1] --> A
I+R freq ( 9 - 9) = -2034.8 [cm-1] --> A I+R
freq ( 10 - 10) = -2025.2 [cm-1] --> A I+R freq ( 11
- 11) = -1864.3 [cm-1] --> A I+R freq ( 12 - 12) =
-1804.5 [cm-1] --> A I+R freq ( 13 - 13) = -1099.4
[cm-1] --> A I+R freq ( 14 - 14) = -947.6 [cm-1]
--> A I+R freq ( 15 - 15) = -912.5 [cm-1] --> A
I+R freq (316 -316) = 179.3 [cm-1] --> A
I+R freq (317 -317) = 193.0 [cm-1] --> A I+R
freq (318 -318) = 215.8 [cm-1] --> A I+R freq (319
-319) = 240.2 [cm-1] --> A I+R freq (320 -320) =
270.4 [cm-1] --> A I+R freq (321 -321) = 317.0
[cm-1] --> A I+R freq (322 -322) = 370.8 [cm-1]
--> A I+R freq (323 -323) = 377.3 [cm-1] --> A
I+R freq (324 -324) = 398.3 [cm-1] --> A
I+R freq (325 -325) = 417.8 [cm-1] --> A I+R
freq (326 -326) = 468.2 [cm-1] --> A I+R freq (327
-327) = 659.0 [cm-1] --> A I+R freq (328 -328) =
1096.6 [cm-1] --> A I+R freq (329 -329) = 1795.5
[cm-1] --> A I+R freq (330 -330) = 2199.3 [cm-1]
--> A I+R
ph.x input file:
phonon calculation at Gamma point.&inputph outdir = './outdir' prefix = 'HS'
tr2_ph = 1.0d-09 epsil = .false. amass(1) = 58.69340 amass(2) = 30.97376
amass(3) = 1.00784 amass(4) = 32.065 fildyn = 'HS.dyn'
alpha_mix(1)=0.1
recover=.true nogg = .true nat_todo = 5
/0.0 0.0 0.0
1 2 37 46 54
scf input file:
&CONTROL calculation = "scf"prefix = 'HS' outdir = './outdir'
pseudo_dir = '/home/'restart_mode = 'from_scratch' forc_conv_thr =
1.0e-03etot_conv_thr= 1e-04 nstep = 999/&SYSTEMibrav = 0 ecutrho
= 200 ecutwfc = 25 nat
= 110 ntyp =
4occupations='smearing',smearing='gaussian',degauss=0.005vdw_corr= 'DFT-D2'
nspin = 2 starting_magnetization(1)= 0.01/&ELECTRONS conv_thr =
1e-8 electron_maxstep = 200mixing_mode='local-TF' mixing_beta =
0.3/&IONS/K_POINTS {automatic}3 3 1 0 0 0ATOMIC_SPECIESNi 58.69340
Ni.pbe-n-rrkjus_psl.0.1.UPFP 30.97376 P.pbe-n-rrkjus_psl.1.0.0.UPFH 1.00784
H.pbe-rrkjus_psl.0.1.UPFS 32.065 S.pbe-n-rrkjus_psl.1.0.0.UPF
CELL_PARAMETERS {angstrom} 11.76538354 0.0000000000
0.0000000000 -5.8826917709 10.189121032 0.0000000000
0.0000000000 0.0000000000 30.993869056ATOMIC_POSITIONS
(angstrom)H 0.879694621 3.392266427 10.708999692S 2.266698845
3.396363162 10.560733430Ni -2.744571590 4.755054131 0.244939179Ni
3.134031329 1.363792691 0.248008546...P -1.060403962 1.841094610
1.604930623P -3.921453199 6.792156181 0.000000000 0 0 0P
1.960697149 3.396027080 0.000000000 0 0 0P 7.842906399
0.000000000 0.000000000 0 0 0
regards
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