CPSCF failed to converge

Hi,
I encountered some error and could you please provide some advice how can I solve this problem. Thank you!
I submitted this input to calculate frequency of excited group state and encountered some error:
here is my input:

 $molecule
0 1
 C        -1.5259467129    1.0059539178    0.6551001428
 N        -2.8701983263    1.0957563236    0.6641567512
 C        -3.4475791071   -0.1059994742    0.2926801401
 C        -2.7482592971   -1.2513683597   -0.0815608481
 N        -1.4200416758   -1.3180396547   -0.0861305039
 C        -0.7867069154   -0.1361602423    0.3268880216
 N         4.8042897450   -0.0089338818    0.0957678788
 C         5.7035350110    0.3320615699    1.1175084503
 C         5.5437268325   -0.3223175655   -1.0532905683
 N        -4.8894992338   -0.0946666737    0.2481825639
 C        -7.5792462896    0.8642364198   -2.7868281047
 C        -7.9848034918    0.5029819885   -1.4696237359
 C        -7.0367972548    0.1959674433   -0.5101394773
 C        -5.6568509872    0.2482417167   -0.8527097126
 C        -5.2210136202    0.5994003641   -2.1335310913
 C        -6.2044381491    0.9033371552   -3.0850188438
 C        -7.0861688880   -0.2028340699    0.9052376788
 C        -8.1001889694   -0.4180351260    1.8209773847
 C        -7.7875504320   -0.7963088592    3.1585663830
 C        -6.4361066298   -0.9452985523    3.5220996911
 C        -5.3874072170   -0.7353713443    2.6159365824
 C        -5.7324065414   -0.3644911805    1.3131642896
 C        -8.6571710446    1.2014387407   -3.8282767459
 C        -8.9372089517   -1.0242833752    4.1513439238
 C        -9.5992850950   -0.0134106772   -3.9991261246
 C        -9.4713204411    2.4195728567   -3.3321123161
 C        -8.0597721186    1.5465796659   -5.2037250002
 C        -9.7673893227    0.2753430718    4.2712414722
 C        -9.8388268264   -2.1668300535    3.6272001774
 C        -8.4352908320   -1.4086963604    5.5543602101
 C         5.4631310839    0.7141435484    2.4411982350
 C         6.5679829217    0.9635216319    3.2602541119
 C         7.9027808866    0.8488443325    2.8080783331
 C         8.1135623718    0.4678634186    1.4740935043
 C         7.0287721344    0.2077759756    0.6281470087
 C         6.9275567714   -0.2034220074   -0.7623399379
 C         7.8750523295   -0.4525297630   -1.7619784437
 C         7.4721025823   -0.8086771905   -3.0586687892
 C         6.0859969785   -0.8978863903   -3.3183855624
 C         5.1142793369   -0.6607823567   -2.3414304413
 C         8.5369514091   -1.0774129228   -4.1402107665
 C         9.4069892808    0.1853948416   -4.3330046745
 C         9.4362246195   -2.2534798346   -3.6968156399
 C         7.9147445164   -1.4392091326   -5.5008006859
 C         9.1138465546    1.1287580029    3.7186153659
 C         9.9998863456   -0.1346676341    3.8007571543
 C         9.9400777800    2.2950569118    3.1310208804
 C         8.6970543217    1.5125152521    5.1501334229
 C         2.6561536599   -1.1406835609   -0.2916432843
 N         1.3211395548   -1.1809626357   -0.2583235195
 C         0.6814374783   -0.1309047683    0.3169569934
 C         1.4538875269    0.8917278390    0.9281357262
 N         2.7841823964    0.9508194953    0.8583608120
 C         3.3926517148   -0.0582120971    0.2112667535
 H        -1.0103544356    1.9397184256    0.9122299101
 H        -3.2935960209   -2.1538189963   -0.3943998141
 H        -9.0491820985    0.4704222632   -1.2196630160
 H        -4.1564672793    0.6333906056   -2.3706030792
 H        -5.8774845528    1.1782559323   -4.0885137760
 H        -9.1448020340   -0.2942392045    1.5217627162
 H        -6.1814208285   -1.2332497669    4.5428729017
 H        -4.3413627334   -0.8498223436    2.9042813311
 H       -10.1110105971   -0.2783414943   -3.0596044927
 H        -9.0433572278   -0.9000631520   -4.3462370072
 H       -10.3752543993    0.2188958166   -4.7474783993
 H        -9.9638017168    2.2226234768   -2.3660467744
 H       -10.2585749955    2.6683257966   -4.0636312601
 H        -8.8252225985    3.3044412715   -3.2101927231
 H        -7.4795616978    0.7079349176   -5.6233221078
 H        -7.4099910880    2.4363857816   -5.1595776160
 H        -8.8760453596    1.7691945622   -5.9099369232
 H       -10.2083177844    0.5767476163    3.3072176400
 H        -9.1465713844    1.1096994688    4.6371567095
 H       -10.5958844173    0.1265853857    4.9838963086
 H       -10.2677269686   -1.9357815170    2.6385420061
 H       -10.6777977768   -2.3330776032    4.3237221053
 H        -9.2735639917   -3.1094048850    3.5405585953
 H        -7.8079879279   -0.6178699492    5.9983316089
 H        -7.8588273270   -2.3487372560    5.5424080834
 H        -9.2976014689   -1.5612095625    6.2236001432
 H         4.4454718361    0.8371832709    2.8145748625
 H         6.3732747216    1.2648854128    4.2921718326
 H         9.1310783080    0.3670948476    1.0821084666
 H         8.9395442899   -0.3581673513   -1.5222900393
 H         5.7398134197   -1.1589896663   -4.3208281634
 H         4.0530315650   -0.7295866505   -2.5920669864
 H         9.9189633178    0.4738852803   -3.4007253653
 H         8.7904584783    1.0405867883   -4.6569394003
 H        10.1795669008    0.0066227010   -5.1013391196
 H         9.9376153366   -2.0433018425   -2.7382054416
 H        10.2182234708   -2.4466520012   -4.4521542978
 H         8.8435945466   -3.1749778225   -3.5707916790
 H         7.2809518322   -0.6252606933   -5.8912891050
 H         7.3049055518   -2.3563965725   -5.4415652208
 H         8.7162854739   -1.6197942497   -6.2370131864
 H        10.3740610107   -0.4350923221    2.8085554880
 H         9.4335806524   -0.9843014605    4.2175237759
 H        10.8751616099    0.0473777455    4.4488869636
 H        10.3066107356    2.0624928812    2.1178801476
 H        10.8181010179    2.5086651246    3.7662956967
 H         9.3315012388    3.2124424185    3.0656346986
 H         8.1212171294    0.7080233235    5.6379827919
 H         8.0894456625    2.4329769074    5.1669053666
 H         9.5962724883    1.6972413800    5.7620437150
 H         3.1682442237   -2.0092903461   -0.7231807398
 H         0.9775714709    1.6899528155    1.5079860428
$end


$rem
JOBTYPE           freq
CIS_N_ROOTS       1  
CIS_SINGLETS      true
CIS_STATE_DERIV   1   Lowest TDDFT state
BASIS             6-31G*
MEM_TOTAL         192000
!CPSCF_NSEG        3  
exchange general
omega 170
lrc_dft true
SET_ITER 100
$end 

$xc_functional
x wpbe 1.0
c pbe 1.0
$end

And here is where I stuck:

 Calculating MO derivatives via CPSCF
 CPSCF will be done in 2 segments to save memory.
   1         0         159      0.110067    0.001099
   2         0         159      0.032920    0.000445
   3         0         159      0.005145    0.000065
   4         0         159      0.000823    0.000011
   5         0         159      0.000111    0.000001
   6       257          64      0.000008    0.000000    Collapsing Subspace
   7       137          22      0.000003    0.000000
   8       137          22      0.000003    0.000000
   9       137          22      0.000003    0.000000
  10       137          22      0.000003    0.000000
  11       137          22      0.000003    0.000000
  12       137          22      0.000003    0.000000
  13       137          22      0.000003    0.000000
  14       137          22      0.000003    0.000000
  15       137          22      0.000003    0.000000
  16       138          21      0.000002    0.000000
  17       138          21      0.000002    0.000000
  18       138          21      0.000002    0.000000
  19       138          21      0.000002    0.000000
  20       138          21      0.000002    0.000000
  21       139          20      0.000002    0.000000
  22       139          20      0.000002    0.000000
  23       139          20      0.000002    0.000000
  24       139          20      0.000002    0.000000
  25       139          20      0.000002    0.000000
  26       139          20      0.000002    0.000000
  27       139          20      0.000002    0.000000
  28       139          20      0.000002    0.000000
  29       139          20      0.000002    0.000000
  30       139          20      0.000002    0.000000
  31       139          20      0.000002    0.000000
  32       139          20      0.000002    0.000000
  33       139          20      0.000002    0.000000
  34       139          20      0.000002    0.000000
  35       140          19      0.000002    0.000000
  36       140          19      0.000002    0.000000
  37       140          19      0.000002    0.000000
  38       140          19      0.000002    0.000000
  39       140          19      0.000002    0.000000
  40       140          19      0.000002    0.000000
  41       140          19      0.000002    0.000000
  42       302          19      0.000002    0.000000    Collapsing Subspace
  43       140          19      0.000002    0.000000
  44       140          19      0.000002    0.000000
  45       140          19      0.000002    0.000000
  46       140          19      0.000002    0.000000
  47       140          19      0.000002    0.000000
  48       140          19      0.000002    0.000000
  49       140          19      0.000002    0.000000
  50       140          19      0.000002    0.000000
  51       140          19      0.000002    0.000000
  52       140          19      0.000002    0.000000
  53       140          19      0.000002    0.000000
  54       140          19      0.000002    0.000000
  55       140          19      0.000002    0.000000
  56       140          19      0.000002    0.000000
  57       140          19      0.000002    0.000000
  58       140          19      0.000002    0.000000
  59       140          19      0.000002    0.000000
  60       140          19      0.000002    0.000000
  61       140          19      0.000002    0.000000
  62       140          19      0.000002    0.000000
  63       140          19      0.000002    0.000000
  64       140          19      0.000002    0.000000
  65       140          19      0.000002    0.000000
  66       140          19      0.000002    0.000000
  67       140          19      0.000002    0.000000
  68       140          19      0.000002    0.000000
  69       140          19      0.000002    0.000000
  70       140          19      0.000002    0.000000
  71       140          19      0.000002    0.000000
  72       140          19      0.000002    0.000000
  73       140          19      0.000002    0.000000
  74       140          19      0.000002    0.000000
  75       140          19      0.000002    0.000000
  76       140          19      0.000002    0.000000
  77       140          19      0.000002    0.000000
  78       140          19      0.000002    0.000000
  79       140          19      0.000002    0.000000
  80       140          19      0.000002    0.000000
  81       140          19      0.000002    0.000000
  82       140          19      0.000002    0.000000
  83       302          19      0.000002    0.000000    Collapsing Subspace
  84       140          19      0.000002    0.000000
  85        94          65      0.000051    0.000005
  86       140          19      0.000002    0.000000
  87        87          72      0.000074    0.000007
  88       140          19      0.000002    0.000000
  89        89          70      0.000042    0.000004
  90       103          56      0.000041    0.000007
  91        94          65      0.000058    0.000006
  92        87          72      0.000074    0.000007
  93        98          61      0.000084    0.000012
  94        94          65      0.000058    0.000006
  95       102          57      0.000036    0.000005
  96        99          60      0.000036    0.000004
  97       105          54      0.000027    0.000004
  98       260          61      0.000045    0.000006    Collapsing Subspace
  99        91          68      0.000046    0.000006
 100        90          69      0.000054    0.000006

If possible, increase MEM_TOTAL so that the CPSCF does not need to be divided into two segments. This may help convergence. Alternatively,

  • CIS_CONVERGENCE controls the CPSCF convergence threshold, and

  • MAX_CIS_CYCLES controls the max iterations

Hi Dr. Herbert,
Thank you so much! The problem was solved with a doubled memory.