Error related to specified geometry - Calculation failed to converge


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Forum Vet
Please add the line

set quickguess t

before the task line and the system will converge.

Here is the modified input file

start tcp

title "TCP"

charge 0

geometry units angstroms print xyz
   C       -3.28602        1.98875       -3.71007
   C       -2.21452        1.34327       -2.88280
   H       -2.91702        2.17184       -4.72387
   H       -3.59895        2.94125       -3.26958
   H       -4.17384        1.35006       -3.76577
   C       -1.29877        2.12505       -2.17102
   C       -0.28598        1.51932       -1.42497
   C       -0.17776        0.12973       -1.38375
   C       -1.05980       -0.65500       -2.11855
   C       -2.07594       -0.04947       -2.86373
   H       -1.36831        3.21014       -2.19138
   H        0.41661        2.13658       -0.87118
   H       -0.98218       -1.73725       -2.14154
   H       -2.75982       -0.67693       -3.43149
   O        0.83874       -0.36919       -0.62363
   P        0.84869       -1.81619        0.09275
   O        2.28191       -1.82589        0.83988
   O       -0.16083       -1.65749        1.34916
   C       -1.51555       -1.67647        1.19218
   C        3.49182       -1.82680        0.20626
   O        0.61858       -3.01099       -0.79121
   C       -2.23553       -0.56837        1.62865
   C       -3.62357       -0.54356        1.48607
   C       -4.29866       -1.63910        0.93325
   C       -2.17203       -2.77681        0.65039
   C        4.60971       -1.69909        1.03064
   C        5.89349       -1.68421        0.48150
   C        6.07051       -1.78876       -0.90202
   C        4.94443       -1.93663       -1.72044
   C        3.65878       -1.95116       -1.17011
   C        7.44863       -1.81040       -1.49355
   H        7.44580       -1.39212       -2.50559
   H        7.82144       -2.83834       -1.53630
   H        8.13981       -1.20739       -0.89533
   H       -1.72052        0.28420        2.06197
   H       -4.17515        0.33654        1.80850
   C       -3.56101       -2.75221        0.50995
   H       -4.06464       -3.61044        0.07048
   H       -1.62009       -3.65762        0.33353
   C       -5.78596       -1.59684        0.74312
   H       -6.26224       -0.99170        1.52168
   H       -6.21654       -2.60183        0.80452
   H       -6.02558       -1.16813       -0.23482
   H        2.81566       -2.07211       -1.84347
   H        5.05983       -2.04468       -2.79706
   H        4.48458       -1.61254        2.10692
   H        6.75307       -1.59083        1.14119
end

basis "ao basis" spherical
 * library "6-31+G*"
end

driver
  maxiter 1000
end


charge 0
dft
  xc b3lyp
  mult 1
  iterations 5000
end

set quickguess t

task dft optimize