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Dear all,

I am calculating the frequencies of the optimized configuration in order to calculate the thermodynamic data. However, there is a imaginary frequency I cannot remove. I have search this problem in the forum and try some methods, such as improving the accuracy by setting PREC = High and further optimizing the configuration by setting EDIFFG = 0.001. However, I still cannot remove the imaginary frequency. Is there any method to remove the imaginary frequency?

Thank you in advance.

My INCAR for frequency calculation is as followed:

ENCUT = 500
ENAUG = 650
PREC = Accurate
IALGO = 48
NELM = 60
NELMIN = 8
NELMDL = -12
EDIFF = 1E-07
#NBANDS = 7
GGA = BF
#VOSKOWN = 1
LREAL = Auto
WEIMIN = 0
NSW = 1
NFREE = 2
POTIM = 0.015
IBRION = 5
ISIF = 2
ISYM = 0
SIGMA = 0.2
ISMEAR = 1
ISPIN = 2
MAGMOM = 10*1 5*1 45*2
LUSE_VDW = .TRUE.
Zab_vdW = -1.8867
AGGAC = 0.0000


and the frequencies:
3064.440613
3057.320861
3047.647488
3028.840544
3012.173099
2999.589185
2986.690730
2974.771172
2921.820971
2916.992874
1489.979955
1484.109314
1466.449324
1445.864904
1426.039448
1398.524274
1367.706888
1334.502598
1322.441696
1265.130272
1240.640539
1181.001079
1148.347565
1078.040908
1039.355932
1025.730247
955.175461
911.402465
879.316641
839.413897
824.161614
749.362491
712.092716
518.539916
427.569516
363.636430
302.360496
251.761076
169.649930
139.544573
132.463482
89.688117
77.834383
37.859043
f/i 31.201882

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