Taken from A new multiplet table for Fe I
Nave G, Johansson S, Learner R, and Thorne A,
Ap. J. Sup. 94, No. 1, pp 221-459.

Neutral iron Fe I energy levels checked HTML to 40000 cm-1
Configuration Term J E(cm-1)
3d64s2 a5D 4 0.000
   3 415.933
   2 704.007
   1 888.132
   0 978.074
 
3d7(4F)4s a5F 5 6928.268
   4 7376.764
   3 7728.059
   2 7985.784
   1 8154.713
 
  a3F 4 11976.238
   3 12560.933
   2 12968.553
 
3d7(4P)4s a5P 3 17550.180
   2 17726.987
   1 17927.381
 
3d64s2 a3P 2 18378.185
   1 19552.477
   0 20037.815
 
3d6(5D)4s4p(3P) z7Do 5 19350.890
old 3d64s(a6D)4p   4 19562.438
   3 19757.031
   2 19912.494
   1 20019.634
 
3d64s2 a3H 6 19390.167
   5 19621.005
   4 19788.250
 
 
  b3F 4 20641.109
   3 20874.481
   2 21038.986
 
3d7(2G)4s a3G 5 21715.731
   4 21999.129
   3 22249.428
 
3d6(5D)4s4p(3P) z7Fo 6 22650.414
old 3d64s(a6D)4p   5 22845.867
   4 22996.672
   3 23110.937
   2 23192.498
   1 23244.836
   0 23270.382
 
3d7(4P)4s b3P 2 22838.321
   1 22946.814
   0 23051.748
 
3d6(5D)4s4p(3P) z7Po 4 23711.454
old 3d64s(a6D)4p   3 24180.860
   2 24506.915
 
3d64s2 b3G 5 23783.617
   4 24118.817
   3 24338.765
 
3d7(2P)4s c3P 2 24335.764
   1 24772.016
   0 25091.597
 
3d7(2G)4s a1G 4 24574.653
 
3d6(5D)4s4p(3P) z5Do 4 25899.987
old 3d64s(a6D)4p   3 26140.177
   2 26339.694
   1 26479.379
   0 26550.477
 
3d7(2H)4s b3H 6 26105.906
   5 26351.038
   4 26627.607
 
3d7(a2D)4s a3D 3 26224.967
   2 26623.733
   1 26406.463
 
3d6(5D)4s4p(3P) z5Fo 5 26874.548
old 3d64s(a6D)4p   4 27166.818
   3 27394.689
   2 27559.581
   1 27666.346
 
3d7(2P)4s a1P 1 27543.001
 
3d7(a2D)4s a1D 2 28604.611
 
3d7(2H)4s a1H 5 28819.952
 
3d6(5D)4s4p(3P) z5Po 3 29056.322
old 3d64s(a6D)4p   2 29469.022
   1 29732.734
 
3d64s2 a1I 6 29313.006
 
  b3D 3 29371.810
   2 29356.742
   1 29320.024
 
  b1G 4 29798.934
 
3d6(5D)4s4p(3P) z3Fo 4 31307.243
old 3d64s(a4D)4p   3 31805.069
   2 32133.989
 
  z3Do 3 31322.611
old 3d64s(a4D)4p   2 31686.349
   1 31937.323
 
3d8 c3F 4 32873.630
   3 33412.715
   2 33765.304
 
3d7(4F)4p y5Do 4 33095.939
   3 33507.121
   2 33801.570
   1 34017.101
   0 34121.601
 
  y5Fo 5 33695.395
   4 34039.514
   3 34328.750
   2 34547.209
   1 34692.146
 
3d6(5D)4s4p(3P) z3Po 2 33946.931
old 3d64s(a4D)4p   1 34362.871
   0 34555.595
 
3d6\4s2 b1D 2 34636.790
 
3d7(4F)4p z5Go 6 34843.955
   5 34782.419
   4 35257.322
   3 35611.623
   2 35856.400
 
  z3Go 5 35379.206
   4 35767.562
   3 36079.370
 
  y3Fo 4 36686.174
   3 37162.744
   2 37521.158
 
3d6(5D)4s4p(1P) y5Po 3 36766.964
   2 37157.564
   1 37409.552
 
3d7(2F)4s d3F 2 36940.588
   3 36975.586
   4 37045.932
 
3d7(4F)4p y3Do 3 38175.352
   2 38678.036
   1 38995.733
 
3d6(5D)4s4p(1P) x5Do 4 39625.801
   3 39969.850
   2 40231.333
   1 40404.515
   0 40491.281
 
3d5(6S)4s2\4p y7Po 4 40421.935
   3 40207.088
   2 40052.032