negative frequency using the grid huge

[DrKNiu]

I want to optimize the structure to an energy minimum with grid huge option and It still has several negative frequencies. May I know how to avoid the negative frequency please? here is some other solutions for metal. https://nwchemgit.github.io/Special_AWCforum/st/id2535/Trouble_with_negative_frequencie....HTML
The input file is as follows.
title "pdi b3lyp 3-21g(d,) geometry optimization"
memory 32 gb
scratch_dir ./scratch
permanent_dir ./perm
#restart
geometry nocenter noautosym noautoz
C -1.03654482 -1.15018255 -3.42618529
C 0.05395608 -0.54116394 -1.31342301
C -1.19548108 -0.06651683 -0.82172140
C -2.30682593 -0.15457013 -1.65189044
C -2.23990850 -0.68826264 -2.94067954
C 1.24254862 -0.48956868 -0.53258066
C -1.25676428 0.49362339 0.53509842
C -0.06527099 0.54301479 1.31270722
C 1.18190247 0.06685658 0.81675033
C -1.33174113 1.56341616 3.14942754
C -2.47948328 1.51121343 2.38847012
C -2.43115200 0.98035581 1.09806156
H -3.11650817 -0.74852546 -3.57276947
H -3.40315106 1.88596186 2.81043056
C 1.32949449 -1.56275885 -3.14877686
C 2.46570914 -1.50458794 -2.37995458
C 2.41827271 -0.97133417 -1.08391429
H 3.39221916 -1.86993916 -2.77921570
C 2.29515232 0.14948964 1.63541249
C 1.04287739 1.14662763 3.42173226
C 2.22608469 0.68589162 2.92921110
H 3.10675670 0.73730481 3.54045318
C -0.11850981 1.08353413 2.62544726
C 0.99497409 1.71056583 4.79740958
C -1.41523386 2.13158704 4.51512410
C 0.11844563 -1.08374135 -2.62536310
C -0.99499962 -1.71060356 -4.79739650
C 1.41521585 -2.13159755 -4.51512116
O 2.43608940 -2.53997960 -4.96655929
O -1.96459032 -1.77112806 -5.48225961
N 0.23713215 -2.16712848 -5.25399836
C 0.29815569 -2.71606953 -6.59230258
C 0.08072135 -4.07638057 -6.76816711
C 0.57188410 -1.86230567 -7.65284063
C 0.14344012 -4.58492105 -8.05828546
C 0.62710584 -2.40521781 -8.92928071
C 0.41457099 -3.75605449 -9.13075245
H -0.02101279 -5.63498559 -8.22197076
H 0.83749910 -1.76540472 -9.76766469
H 0.46037708 -4.16384013 -10.12501667
C -0.21613266 -4.98655156 -5.60053514
H -0.35466169 -6.00483637 -5.94285670
C 0.80237298 -0.38537327 -7.43728987
H -0.07140584 0.08767103 -6.99985889
N -0.23714632 2.16714408 5.25399187
C -0.29816934 2.71602634 6.59232047
C -0.57192824 1.86223382 7.65282708
C -0.08067476 4.07632144 6.76823809
C -0.62706007 2.40508895 8.92929543
C -0.14329768 4.58480364 8.05838472
C -0.41441273 3.75589801 9.13082618
H -0.83747004 1.76525293 9.76765778
H 0.02121474 5.63485244 8.22211284
H -0.46013714 4.16363545 10.12511345
C -0.80249838 0.38531992 7.43723256
H -1.64762339 0.21003608 6.77893636
C 0.21618613 4.98652537 5.60063639
H -0.59823250 4.98405245 4.88290688
O 1.96457847 1.77113646 5.48224885
O -2.43609087 2.54003963 4.96653430
H -1.00955312 -0.10618233 8.38019379
H 0.07150181 -0.08787065 7.00038538
H 1.12272823 4.68361915 5.08636618
H 0.35402020 6.00492027 5.94290971
H 1.64789599 -0.21003373 -6.77951190
H 1.00875167 0.10622447 -8.38034930
H -1.12228557 -4.68322639 -5.08583128
H 0.59860679 -4.98458360 -4.88316071
H -3.33171989 0.94845070 0.52556362
H 3.24895477 -0.19802131 1.29507303
H 3.33171373 -0.94838413 -0.52558656
H -3.24895591 0.19808666 -1.29510230

end

basis

• library 3-21g*
  end
  dft
  grid huge
  xc b3lyp
  end
  scf
  maxiter 200
  semidirect memsize 400000000 filesize 0
  end
  task dft optimize
  task dft freq numerical

The output for the frequency part is shown below.

Normal Eigenvalue || Derivative Dipole Moments (debye/angs)
Mode [cm**-1] || [d/dqX] [d/dqY] [d/dqZ]
------ ---------- || ------------------ ------------------ -----------------
1 -62.265 || 0.291 -0.082 0.025
2 -52.276 || 0.045 0.003 -0.003
3 -48.760 || -0.030 0.029 -0.005
4 -29.153 || 0.076 -0.021 -0.015
5 -22.550 || 0.050 0.018 -0.047
6 -18.472 || 0.066 0.006 0.007
7 8.414 || 0.082 -0.001 0.007
8 14.080 || -0.050 0.028 -0.010
9 30.825 || -0.047 0.009 -0.002
10 42.290 || 0.029 0.040 0.084
11 47.319 || -0.037 0.007 -0.057
12 51.165 || -0.022 -0.091 0.008
13 55.284 || 0.068 0.226 -0.022
14 66.026 || 0.024 0.017 0.006
15 76.553 || -0.004 -0.006 0.003
16 92.047 || 0.184 0.025 0.007
17 95.885 || 0.026 0.031 -0.040

[edoapra]

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