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Comparison of levels of theory for C-C


Click on an entry for a histogram of the values.
The subscript refers to how many bonds of that type have been calculated.
average calculated bond lengths (Å)
Methods with predefined basis sets
semi-empirical AM1 1.4694
867
PM3 1.4704
834
PM6 1.4911
2163
composite G2 1.4707
1722
G3 1.4780
1986
G3B3 1.4794
2161
G3MP2 1.4339
77
G4 1.4664
2008
CBS-Q 1.4720
1408
molecular mechanics DREIDING 1.5414
17

average calculated bond lengths (Å)
Methods with standard basis sets
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
hartree fock HF 1.4750
1969
1.4688
2095
1.4719
2001
1.4629
2006
1.4670
2388
1.4613
2002
1.4524
1152
1.4609
1997
1.4600
1982
1.4621
1969
1.4561
1232
1.4152
8
1.4803
2211
1.4787
2558
1.4625
2011
1.4577
1934
1.4260
243
1.4643
1779
1.4610
1690
1.4289
162
1.4031
18
1.3496
7
1.3435
8
  1.3626
3
1.3544
3
1.4545
36
ROHF 1.4488
45
1.4509
138
1.4535
126
1.4433
122
1.4475
143
1.4500
129
1.4474
136
1.4458
136
1.4464
113
1.4506
50
1.3545
9
  1.4195
51
1.2940
4
1.4488
136
1.4444
136
1.4445
54
1.4430
102
1.4397
88
1.4326
44
    1.3504
1
       
density functional LSDA 1.4700
1103
1.4529
1365
1.4518
1109
1.4494
1140
1.4455
1450
1.4455
1417
1.4468
1420
1.4418
1442
1.4419
1410
1.4426
1404
1.4033
41
1.4118
8
1.4344
383
1.3580
9
1.4472
1417
1.4397
1409
1.3810
23
1.4465
1221
1.4347
412
1.3990
20
  1.3302
1
1.3209
1
  1.3672
3
1.3563
3
 
BLYP 1.5084
1961
1.4900
2035
1.4875
1594
1.4828
2030
1.4911
2450
1.4784
2035
1.4799
2018
1.4720
1587
1.4775
1957
1.4784
1923
1.4087
47
1.4340
8
1.4613
647
1.3504
15
1.4802
1983
1.4747
2009
1.3590
3
1.4881
1147
1.4705
230
1.3593
3
  1.3420
1
1.3333
1
  1.3841
3
1.3741
3
 
B1B95 1.4822
1992
1.4644
1741
1.4664
2011
1.4641
2017
1.4614
1959
1.4605
2017
1.4605
2041
1.4576
2001
1.4584
1995
1.4597
1929
1.3926
47
1.4159
8
1.4429
659
1.3356
15
1.4603
2006
1.4546
2004
1.4290
46
1.4630
1682
1.4483
950
1.4344
36
  1.3950
2
1.3889
2
  1.2510
1
1.2788
2
 
B3LYP 1.4960
1988
1.4807
2068
1.4792
2033
1.4711
2032
1.4668
2104
1.4674
2033
1.4704
2079
1.4657
2023
1.4593
1048
1.4697
2210
1.4693
983
1.4231
8
1.4882
2260
1.4854
2558
1.4685
2024
1.4645
2011
1.4345
209
1.4637
1076
1.4793
2043
1.4332
163
1.4118
18
1.3608
7
1.3522
8
  1.3734
3
1.3637
3
1.4625
36
B3LYPultrafine 1.4333
10
1.5067
340
1.4061
11
1.4064
11
1.4719
1825
1.4661
332
1.4594
471
1.4640
332
1.3974
11
1.3725
24
1.3989
47
1.4231
8
1.4627
346
1.3401
15
1.4601
542
1.4556
977
1.3486
3
1.4577
429
1.4614
1832
1.3488
3
  1.3325
1
1.3399
2
  1.3734
3
1.3637
3
 
B3PW91 1.4795
1041
1.4703
1997
1.4712
1986
1.4688
1992
1.4659
1954
1.4662
1987
1.4616
1555
1.4625
1966
1.4577
996
1.4654
1903
1.3968
47
1.4201
8
1.4493
622
1.3392
15
1.4659
1985
1.4611
1975
1.3471
3
1.4733
1156
1.4633
256
1.3472
3
  1.3313
1
1.3234
1
  1.3711
3
1.3620
3
 
mPW1PW91 1.4749
1116
1.4669
2005
1.4605
1230
1.4648
1998
1.4626
1988
1.4617
2007
1.4627
2016
1.4597
2019
1.4601
1972
1.4620
1923
1.3950
47
1.4181
8
1.4462
640
1.3374
15
1.4622
2005
1.4529
1332
1.3451
3
1.4661
1408
1.4451
421
1.3453
3
  1.3293
1
1.3216
1
  1.3690
3
1.3601
3
 
M06-2X 1.4730
658
1.4616
654
1.4919
2505
1.4580
658
1.4840
2055
1.4551
652
1.4561
657
1.4541
657
1.4537
658
1.4538
742
1.3971
47
1.4196
8
1.4509
617
1.3374
15
1.4562
656
1.4517
748
1.3458
3
1.4544
477
1.4495
511
1.3460
3
  1.3288
1
1.3213
1
  1.3694
3
1.3607
3
 
PBEPBE 1.4876
1083
1.4801
1966
1.4711
1092
1.4689
1093
1.4776
1948
1.4709
1980
1.4721
1978
1.4689
1992
1.4693
1979
1.4711
1915
1.4717
1037
1.4283
8
1.4558
639
1.4860
2538
1.4717
1949
1.4666
1967
1.4404
45
1.4665
503
1.4607
567
1.4419
36
  1.3397
1
1.3323
1
  1.3798
3
1.3708
3
1.4685
36
PBEPBEultrafine 1.4372
10
1.4771
331
1.4333
10
1.4315
10
1.4735
1622
1.4709
331
1.4715
331
1.4689
330
1.4224
10
1.3873
23
1.4046
47
1.4283
8
1.4666
346
1.3484
15
1.4639
551
1.4580
547
1.3556
3
1.4627
415
1.4542
402
1.3558
3
  1.3397
1
1.3323
1
  1.3798
3
1.3708
3
 
PBE1PBE 1.4683
631
1.4564
585
1.4543
631
1.4523
636
1.4816
2086
1.4490
635
1.4494
635
1.4465
635
1.4462
636
1.4471
634
1.3953
47
1.4184
8
1.4461
623
1.3379
15
1.4496
635
1.4440
635
1.3457
3
1.4509
451
1.4448
410
1.3459
3
  1.3299
1
1.3226
1
  1.3693
3
1.3607
3
 
HSEh1PBE 1.4752
653
1.4924
2096
1.4589
653
1.4570
654
1.4824
2048
1.4537
653
1.4830
2078
1.4517
653
1.4514
654
1.4522
652
1.3951
47
1.4182
8
1.4487
613
1.3377
15
1.4546
653
1.4846
2084
1.3457
3
1.4528
473
1.4454
415
1.3458
3
  1.3298
1
1.3223
1
  1.3694
3
1.3605
3
 
TPSSh 1.5004
128
1.4699
372
1.4707
372
1.4678
373
1.4974
2189
1.4637
372
1.4977
2181
1.4616
372
1.4735
128
1.4836
2145
1.3968
37
  1.4654
341
1.3430
15
1.4646
372
1.4920
2183
1.3719
27
1.4579
325
1.4547
299
1.3807
25
  1.3340
1
1.3457
2
  1.3753
3
1.3665
3
 
wB97X-D 1.4948
165
1.4763
165
1.4859
2458
1.4752
165
1.4813
2472
1.4721
164
1.4827
2470
1.4705
164
1.4797
2458
1.4715
163
1.3930
37
  1.4778
2470
1.3376
15
1.4827
2470
1.4758
2472
1.3682
27
1.4703
156
1.4795
2315
1.3680
26
        1.3696
3
1.3604
3
 
B97D3 1.5379
79
1.4950
2428
1.5245
79
1.5205
79
1.4912
2426
1.5152
78
1.4919
2429
1.5164
77
1.4886
2428
1.5158
77
1.4959
2465
  1.5110
78
1.3470
15
1.5165
78
1.4855
2426
1.3746
24
1.5155
78
1.4896
2200
1.3670
24
        1.3799
3
1.3705
3
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 1.5017
1051
1.4821
2044
1.4807
1970
1.4812
1974
1.4865
2376
1.4702
1991
1.4755
2035
1.4902
2319
1.4736
1961
1.4705
1518
1.4021
47
1.4256
8
1.4894
2227
1.4853
2472
1.4784
2001
1.4665
1607
1.3895
82
1.4768
1032
1.4535
903
1.3857
77
1.4104
17
1.3491
9
1.3384
10
  1.3866
3
1.3712
3
1.4682
36
MP2=FULL 1.5002
1038
1.4738
1338
1.4744
1223
1.4750
1225
1.4709
2063
1.4659
1528
1.4668
1557
1.4709
1961
1.4719
988
1.4612
1066
1.3986
47
1.4219
8
1.4693
640
1.3416
15
1.4753
1327
1.4581
1361
1.3842
81
1.4689
562
1.4637
582
1.3850
78
1.4101
18
1.3480
9
1.3358
10
  1.3855
3
1.3663
3
1.4666
36
ROMP2 1.4630
67
1.4492
58
1.4499
56
1.4526
59
1.4334
59
1.4330
59
1.4341
59
1.4360
59
1.4363
59
1.4324
58
1.3910
5
  1.4257
38
1.3106
1
1.4430
59
1.4320
55
1.4142
12
1.4387
56
1.3412
13
1.4137
12
          1.3332
1
 
MP3 1.4408
10
1.4332
10
1.4332
10
1.4351
10
1.4676
1850
1.4172
10
1.4930
2162
1.4208
10
1.4211
10
1.4168
10
1.4014
47
1.4251
8
1.4583
318
1.3404
15
1.4700
318
1.4352
310
1.3490
3
1.4308
10
1.4160
10
1.1968
1
  1.3415
1
1.3281
1
  1.3825
3
1.3666
3
 
MP3=FULL   1.4951
137
1.4964
137
1.4956
137
1.4930
2139
1.4784
136
1.4932
1999
1.4816
136
1.4800
137
1.4752
135
1.3939
36
  1.4377
297
1.3383
15
1.4728
305
1.4327
281
  1.4326
123
1.3816
63
    1.3406
1
1.3259
1
  1.3815
3
1.3620
3
 
MP4 1.4163
29
1.4645
615
1.4767
25
1.4992
56
1.4472
677
1.4317
11
1.4339
11
1.3947
14
1.4387
461
1.3685
20
1.4138
34
1.4314
8
1.4335
307
1.2622
4
1.4447
344
1.4169
261
1.3573
3
1.4361
266
1.4038
138
1.3577
3
  1.3494
1
1.3564
2
  1.3182
2
1.2999
2
 
MP4=FULL 1.4430
10
1.4603
367
1.4394
10
1.4403
10
1.4437
379
1.4209
10
1.4236
10
1.4249
10
1.4400
326
1.4177
10
1.4113
33
1.4277
8
1.4296
9
1.2600
4
1.4456
341
1.4157
205
1.3541
3
1.4391
246
1.3862
116
1.3543
3
  1.3484
1
1.3539
2
  1.3172
2
1.2948
2
 
B2PLYP 1.4882
403
1.4696
403
1.4703
403
1.4698
403
1.4937
1873
1.4620
402
1.4610
427
1.4618
402
1.4607
401
1.4582
526
1.3936
40
1.3278
1
1.4590
400
1.3425
15
1.4657
402
1.4822
1893
1.3266
1
1.4622
350
1.4373
424
1.3270
1
  1.3365
1
1.3435
2
  1.3779
3
1.3667
3
 
B2PLYP=FULL 1.4880
399
1.4680
429
1.4703
399
1.4698
399
1.4607
428
1.4616
398
1.4613
428
1.4613
398
1.4608
399
1.4593
397
1.3952
37
  1.4585
398
1.3419
15
1.4654
398
1.4570
395
  1.4619
347
1.4521
321
    1.3362
1
1.3427
2
  1.3774
3
1.3653
3
 
B2PLYP=FULLultrafine 1.4998
178
1.4814
178
1.4827
178
1.4808
178
1.4811
1213
1.4731
177
1.4740
177
1.4729
177
1.4715
178
1.4713
176
1.3952
37
  1.4701
177
1.3419
15
1.4770
177
1.4680
177
  1.4799
155
1.4687
160
      1.3591
1
  1.3775
3
1.3653
3
 
Configuration interaction CID 1.3986
23
1.4640
1037
1.4667
958
1.4667
960
1.4596
1467
1.4530
36
1.4540
20
1.4569
905
1.4179
35
1.3552
20
1.3937
47
1.4180
8
1.4207
9
1.3331
15
1.3894
29
1.3761
32
1.3436
3
1.4243
10
1.4100
10
1.1917
1
  1.3356
1
1.3217
1
  1.3767
3
1.3610
3
 
CISD 1.4084
24
1.4653
1025
1.4677
962
1.4674
964
1.4684
1416
1.4885
26
1.4468
18
1.4568
925
1.4185
35
1.3647
19
1.3944
47
1.4187
8
1.4217
9
1.3346
15
1.3906
29
1.3771
32
1.3446
3
1.4251
10
1.4108
10
1.1932
1
  1.3369
1
1.3230
1
  1.3777
3
1.3621
3
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Quadratic configuration interaction QCISD 1.4593
122
1.4915
1650
1.4836
1033
1.4810
1067
1.4673
1338
1.4598
1064
1.4608
952
1.4655
1125
1.4593
980
1.4550
773
1.4037
47
1.4265
8
1.4428
573
1.3451
15
1.4685
965
1.4364
633
1.3541
4
1.4477
402
1.4252
319
1.2817
2
  1.3451
1
1.3482
2
  1.3854
3
1.3692
3
 
QCISD(T) 1.4481
10
1.4648
13
1.4526
11
1.4517
11
1.4436
603
1.4335
11
1.4070
17
1.4318
119
1.3941
26
1.4235
10
1.4142
34
1.4310
8
1.4303
316
1.2661
4
1.4472
416
1.4182
272
1.3560
3
1.4304
282
1.3887
137
1.3565
3
  1.3503
1
1.3537
2
  1.3159
2
1.2968
2
 
QCISD(T)=FULL         1.4363
216
  1.4384
209
      1.4090
25
    1.2638
4
1.4439
208
1.3931
119
1.2581
17
1.4303
160
1.3459
57
1.2200
13
    1.3681
1
  1.3149
2
1.2918
2
 
QCISD(TQ) 1.4488
10
1.4425
10
1.4295
9
1.4317
9
1.3771
39
1.4245
10
1.3351
31
1.4163
9
1.4285
10
1.4240
8
1.3952
10
1.4337
2
1.4839
6
1.3176
1
1.3830
35
1.2778
19
1.2958
8
1.3344
31
1.3089
10
1.2888
3
             
QCISD(TQ)=FULL         1.3143
22
  1.2693
16
      1.3219
3
    1.3156
1
1.3243
24
1.2313
13
1.2822
5
1.2848
20
1.3122
8
1.2931
4
             
Coupled Cluster CCD 1.4583
117
1.4779
1065
1.4803
996
1.4786
1042
1.4725
1580
1.4542
983
1.4619
902
1.4632
1004
1.4540
728
1.4485
694
1.4049
46
1.4249
8
1.4401
567
1.3478
14
1.4695
915
1.4313
546
1.3523
4
1.4401
418
1.4095
265
1.2797
2
  1.3985
5
1.3819
6
  1.4421
2
1.4285
2
 
CCSD 1.4477
10
1.4609
13
1.4485
11
1.4484
11
1.4559
815
1.3730
22
1.3670
28
1.3685
26
1.3592
34
1.4617
309
1.4033
47
1.4260
8
1.4530
450
1.3444
15
1.4657
541
1.4366
492
1.2846
28
1.4624
313
1.4227
240
1.3079
14
  1.3445
1
1.3475
2
  1.3848
3
1.3685
3
 
CCSD=FULL 1.4474
10
1.4389
10
1.4389
10
1.4402
10
1.4576
563
1.4194
10
1.4217
10
1.4226
10
1.4228
10
1.4341
308
1.3999
47
1.3757
5
1.4354
443
1.3421
15
1.4616
482
1.4255
441
1.2833
28
1.4387
297
1.4142
226
1.2866
13
  1.3435
1
1.3279
1
  1.3837
3
1.3636
3
 
CCSD(T) 1.4482
10
1.4499
14
1.4524
11
1.4516
11
1.4449
658
1.4332
158
1.4142
63
1.4341
134
1.3994
72
1.4156
56
1.4105
36
1.4307
8
1.4366
318
1.2655
4
1.4461
435
1.4082
269
1.2889
27
1.4309
296
1.3759
137
1.2819
24
  1.3306
9
1.3030
9
  1.3156
2
1.2964
2
 
CCSD(T)=FULL 1.4479
10
1.4423
10
1.4423
10
1.4432
10
1.4418
440
1.4228
10
1.4253
10
1.4348
8
1.4268
10
1.4193
10
1.3820
24
1.4270
8
1.4329
328
1.2633
4
1.4495
373
1.4073
227
1.3138
32
1.4299
228
1.3777
103
1.2713
23
  1.3296
9
1.3171
10
1.3912
1
1.3146
2
1.2915
2
 
STO-3G 3-21G 3-21G* 6-31G 6-31G* 6-31G** 6-31+G** 6-311G* 6-311G** 6-31G(2df,p) 6-311+G(3df,2p) 6-311+G(3df,2pd) TZVP Def2TZVPP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
daug-cc-pVDZ daug-cc-pVTZ daug-cc-pVQZ Sadlej_pVTZ CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.3626
3
1.3544
3
  1.4545
36
1.4832
2036
1.4787
2011
1.4758
2043
1.4699
2017
1.4703
2039
1.4702
2043
ROHF         1.4195
2
1.4140
2
1.4099
2
1.4001
2
1.4037
2
1.4034
2
density functional LSDA 1.3672
3
1.3563
3
    1.4554
10
1.4478
10
1.4423
10
1.4313
10
1.4282
10
1.4280
10
BLYP 1.3841
3
1.3741
3
    1.4654
10
1.4571
10
1.4536
10
1.4420
10
1.4488
10
1.4491
10
B1B95 1.2510
1
1.2788
2
    1.4885
1216
1.4830
1220
1.4697
44
1.4711
38
1.4630
44
1.4630
44
B3LYP 1.3734
3
1.3637
3
  1.4625
36
1.4974
2032
1.4911
2000
1.4890
2027
1.4815
1990
1.4821
2020
1.4826
2006
B3LYPultrafine 1.3734
3
1.3637
3
    1.4867
13
1.4778
13
1.4761
13
1.4651
13
1.4702
13
1.4704
13
B3PW91 1.3711
3
1.3620
3
    1.4511
10
1.4437
10
1.4386
10
1.4278
10
1.4336
10
1.4337
10
mPW1PW91 1.3690
3
1.3601
3
    1.4487
10
1.4413
10
1.4361
10
1.4255
10
1.4313
10
1.4314
10
M06-2X 1.3694
3
1.3607
3
    1.4480
10
1.4418
10
1.4336
10
1.4236
10
1.4318
10
1.4317
10
PBEPBE 1.3798
3
1.3708
3
  1.4685
36
1.4587
10
1.4511
10
1.4461
10
1.4354
10
1.4420
10
1.4423
10
PBEPBEultrafine 1.3798
3
1.3708
3
    1.4587
10
1.4511
10
1.4461
10
1.4354
10
1.4420
10
1.4423
10
PBE1PBE 1.3693
3
1.3607
3
    1.4485
10
1.4412
10
1.4359
10
1.4255
10
1.4313
10
1.4313
10
HSEh1PBE 1.3694
3
1.3605
3
    1.4489
10
1.4417
10
1.4365
10
1.4261
10
1.4313
10
1.4313
10
TPSSh 1.3753
3
1.3665
3
               
wB97X-D 1.3696
3
1.3604
3
    1.5001
165
1.4950
164
1.4893
165
1.4826
164
1.4836
165
1.4837
165
B97D3 1.3799
3
1.3705
3
               
Moller Plesset perturbation MP2 1.3866
3
1.3712
3
  1.4682
36
1.5167
2053
1.4880
2005
1.5005
2000
1.4776
1968
1.4960
2029
1.4956
2032
MP2=FULL 1.3855
3
1.3663
3
  1.4666
36
1.4725
10
1.4494
10
1.4565
10
1.4316
10
1.4543
10
1.4539
10
ROMP2   1.3332
1
    1.4359
2
1.4163
2
1.4212
2
1.3994
2
1.4180
2
1.4176
2
MP3 1.3825
3
1.3666
3
    1.4719
10
1.4502
10
1.4556
10
1.4320
10
1.4530
10
1.4526
10
MP3=FULL 1.3815
3
1.3620
3
               
MP4 1.3182
2
1.2999
2
    1.4763
10
1.4546
10
1.4607
10
1.4370
10
1.4578
10
1.4574
10
MP4=FULL 1.3172
2
1.2948
2
    1.4763
10
1.4546
10
1.4607
10
1.4370
10
1.4575
10
1.4571
10
B2PLYP 1.3779
3
1.3667
3
    1.4071
3
1.3972
3
1.3923
3
1.3786
3
1.3874
3
1.3873
3
B2PLYP=FULL 1.3774
3
1.3653
3
               
B2PLYP=FULLultrafine 1.3775
3
1.3653
3
               
Configuration interaction CID 1.3767
3
1.3610
3
    1.4664
10
1.4451
10
1.4504
10
1.4270
10
1.4477
10
1.4473
10
CISD 1.3777
3
1.3621
3
    1.4674
10
1.4460
10
1.4514
10
1.4280
10
1.4488
10
1.4483
10
Quadratic configuration interaction QCISD 1.3854
3
1.3692
3
    1.4774
10
1.4539
10
1.4612
10
1.4359
10
1.4585
10
1.4581
10
QCISD(T) 1.3159
2
1.2968
2
    1.4801
10
1.4571
10
1.4641
10
1.4394
10
1.4612
10
1.4608
10
QCISD(T)=FULL 1.3149
2
1.2918
2
               
QCISD(TQ)         1.4807
10
1.4575
10
1.4644
10
1.4395
10
1.4617
10
1.4612
10
Coupled Cluster CCD 1.4421
2
1.4285
2
    1.4745
10
1.4511
10
1.4582
10
1.4329
10
1.4555
10
1.4550
10
CCSD 1.3848
3
1.3685
3
    1.4772
10
1.4535
10
1.4608
10
1.4354
10
1.4582
10
1.4577
10
CCSD=FULL 1.3837
3
1.3636
3
    1.4772
10
1.4535
10
1.4608
10
1.4354
10
1.4579
10
1.4573
10
CCSD(T) 1.3156
2
1.2964
2
    1.4801
10
1.4570
10
1.4640
10
1.4391
10
1.4611
10
1.4607
10
CCSD(T)=FULL 1.3146
2
1.2915
2
    1.4801
10
1.4570
10
1.4640
10
1.4391
10
1.4608
10
1.4603
10
For descriptions of the methods (AM1, HF, MP2, ...) and basis sets (3-21G, 3-21G*, 6-31G, ...) see the glossary in section I.C. Predefined means the basis set used is determined by the method.