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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 1.4696
1222
PM3 1.4661
989
PM6 1.4816
2306
composite G2 1.4506
1151
G3 1.4471
1291
G3B3 1.4650
2350
G3MP2 1.4291
116
G4 1.4619
2209
CBS-Q 1.4467
1284
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 cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
hartree fock HF 1.4679
2230
1.4564
2344
1.4587
2249
1.4561
2261
1.4823
2547
1.4545
2258
1.4452
1467
1.4542
2253
1.4534
2249
1.4548
2237
1.4520
1406
1.4152
8
1.4678
2463
1.4558
2269
1.4507
2189
1.4288
363
1.4582
1951
1.4545
1846
1.4298
310
1.4164
22
1.2932
1
1.3496
7
1.3782
12
1.2092
2
1.4486
38
1.4369
157
1.4778
1830
ROHF 1.4620
42
1.4517
150
1.4542
138
1.4442
134
1.4502
153
1.4511
140
1.4481
147
1.4473
147
1.4454
129
1.4634
47
1.3897
31
  1.4160
73
1.4502
147
1.4458
147
1.4317
74
1.4441
113
1.4388
105
1.4215
64
      1.3504
1
1.2465
1
  1.4104
17
1.4031
17
density functional LSDA 1.4630
1290
1.4464
1551
1.4448
1304
1.4430
1327
1.4400
1624
1.4385
1612
1.4410
1603
1.4363
1617
1.4363
1592
1.4369
1586
1.4217
113
1.4118
8
1.4224
579
1.4403
1615
1.4329
1606
1.3810
23
1.4414
1292
1.4224
505
1.3990
20
1.4567
6
1.3011
1
1.3302
1
1.3803
4
1.2286
2
1.3499
2
1.3855
4
1.3756
4
BLYP 1.5019
2222
1.4772
2285
1.4727
1858
1.4766
2285
1.4841
2609
1.4722
2291
1.4736
2274
1.4652
1860
1.4710
2219
1.4717
2185
1.4471
309
1.4340
8
1.4506
1029
1.4738
2239
1.4682
2264
1.3590
3
1.4761
1364
1.4472
508
1.3593
3
1.4824
6
1.3136
1
1.3420
1
1.4003
4
1.2361
2
1.3669
2
1.4570
157
1.4527
153
B1B95 1.4760
2260
1.4580
2023
1.4603
2270
1.4580
2282
1.4548
2227
1.4543
2282
1.4553
2212
1.4514
2267
1.4521
2262
1.4517
2221
1.4286
317
1.4159
8
1.4336
951
1.4544
2264
1.4485
2269
1.4290
46
1.4570
1842
1.4399
1168
1.4344
36
1.4658
6
1.3008
1
1.3950
2
1.3989
5
1.2248
2
  1.4321
117
1.4293
138
B3LYP 1.4893
2250
1.4680
2325
1.4667
2286
1.4650
2292
1.4607
2359
1.4612
2293
1.4612
2338
1.4596
2283
1.4517
1395
1.4637
2456
1.4630
1160
1.4231
8
1.4758
2513
1.4624
2285
1.4583
2274
1.4346
347
1.4569
1258
1.4679
2199
1.4349
309
1.4170
21
1.3043
1
1.3608
7
1.3686
11
1.2256
2
1.4569
38
1.4460
157
1.4420
153
B3LYPultrafine 1.4333
10
1.4477
721
1.4061
11
1.4064
11
1.4643
2089
1.4438
721
1.4445
841
1.4417
722
1.3974
11
1.4378
263
1.4357
316
1.4231
8
1.4407
734
1.4468
925
1.4458
1314
1.3486
3
1.4455
700
1.4559
2008
1.3488
3
1.4728
6
1.3043
1
1.3325
1
1.3833
5
1.2256
2
1.3559
2
1.4451
155
1.4438
146
B3PW91 1.4721
1388
1.4637
2255
1.4645
2242
1.4625
2248
1.4593
2210
1.4597
2242
1.4563
1728
1.4561
2222
1.4494
1343
1.4587
2161
1.4330
317
1.4201
8
1.4379
1004
1.4597
2240
1.4547
2230
1.3471
3
1.4620
1370
1.4372
539
1.3472
3
1.4699
6
1.3037
1
1.3313
1
1.3881
4
1.2273
2
1.3540
2
1.4427
157
1.4393
153
mPW1PW91 1.4680
1464
1.4604
2262
1.4526
1547
1.4588
2256
1.4563
2242
1.4556
2262
1.4577
2181
1.4536
2275
1.4540
2233
1.4546
2199
1.4310
317
1.4181
8
1.4354
1022
1.4563
2260
1.4453
1619
1.3451
3
1.4577
1596
1.4322
713
1.3453
3
1.4678
6
1.3020
1
1.3293
1
1.3860
4
1.2256
2
1.3516
2
1.4404
157
1.4373
153
M06-2X 1.4605
1040
1.4498
1034
1.4799
2644
1.4463
1038
1.4709
2319
1.4429
1033
1.4453
947
1.4419
1039
1.4416
1039
1.4423
1107
1.4633
1645
1.4196
8
1.4399
909
1.4444
1037
1.4415
1022
1.3458
3
1.4430
747
1.4378
766
1.3460
3
1.4710
6
1.3025
1
1.3288
1
1.3874
4
1.2235
2
1.3517
2
1.4413
155
1.4385
151
PBEPBE 1.4807
1430
1.4736
2227
1.4640
1444
1.4619
1443
1.4652
2199
1.4649
2239
1.4660
2237
1.4628
2252
1.4635
2238
1.4645
2184
1.5327
1439
1.4283
8
1.4452
1021
1.4656
2208
1.4604
2226
1.4404
45
1.4536
779
1.4476
828
1.4419
36
1.4766
6
1.3125
1
1.3397
1
1.3960
4
1.2386
2
1.4629
38
1.4509
157
1.4476
153
PBEPBEultrafine 1.4372
10
1.4549
721
1.4333
10
1.4315
10
1.4650
1912
1.4492
719
1.4502
711
1.4469
719
1.4224
10
1.4443
262
1.4409
317
1.4283
8
1.4454
734
1.4512
932
1.4450
929
1.3556
3
1.4501
686
1.4421
672
1.3558
3
1.4766
6
1.3125
1
1.3397
1
1.3960
4
1.2386
2
1.3628
2
1.4509
157
1.4494
146
PBE1PBE 1.4561
1030
1.4451
972
1.4440
1014
1.4421
1018
1.4688
2349
1.4386
1017
1.4390
1017
1.4362
1018
1.4360
1018
1.4368
1016
1.4312
317
1.4184
8
1.4352
1005
1.4395
1017
1.4338
1017
1.3457
3
1.4397
722
1.4320
702
1.3459
3
1.4680
6
1.3030
1
1.3299
1
1.3864
4
1.2270
2
1.3518
2
1.4405
157
1.4338
157
HSEh1PBE 1.4627
1036
1.4812
2365
1.4463
1034
1.4452
1035
1.4692
2314
1.4416
1034
1.4700
2336
1.4396
1035
1.4394
1035
1.4401
1033
1.4311
317
1.4182
8
1.4378
905
1.4428
1034
1.4734
2352
1.3457
3
1.4412
744
1.4330
685
1.3458
3
1.4677
6
1.3027
1
1.3298
1
1.3861
4
1.2266
2
1.3516
2
1.4404
157
1.4373
153
TPSSh 1.4636
438
1.4506
763
1.4514
762
1.4495
763
1.4892
2495
1.4451
762
1.4816
2330
1.4431
762
1.4373
436
1.4754
2299
1.4373
315
  1.4422
735
1.4451
831
1.4759
2332
1.4287
187
1.4438
604
1.4369
596
1.4306
185
1.4745
6
1.3073
1
1.3340
1
1.3868
5
1.2311
2
1.3573
2
1.4471
152
1.4430
151
wB97X-D 1.4609
475
1.4426
474
1.4746
2590
1.4419
473
1.4698
2603
1.4382
469
1.4704
2612
1.4363
473
1.4682
2590
1.4331
486
1.4331
315
  1.4664
2602
1.4714
2599
1.4644
2603
1.4263
177
1.4398
439
1.4675
2420
1.4197
163
1.4706
6
1.3010
1
  1.4095
3
1.2234
2
1.3532
2
1.4426
158
1.4389
153
B97D3 1.4721
384
1.4828
2572
1.4519
382
1.4505
379
1.4790
2570
1.4412
396
1.4848
2568
1.4394
395
1.4817
2568
1.4397
395
1.4782
2546
  1.4767
2578
1.4427
396
1.4741
2551
1.4308
171
1.4436
375
1.4781
2311
1.4125
149
1.4770
6
1.3112
1
  1.4169
3
1.2357
2
1.3624
2
1.4510
156
1.4877
1363
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 cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2 1.4826
1388
1.4765
2299
1.4763
2134
1.4754
2228
1.4744
2522
1.4593
2147
1.4646
2195
1.4782
2458
1.4631
2121
1.4582
1710
1.4376
316
1.4256
8
1.4740
2375
1.4676
2157
1.4540
1786
1.4243
234
1.4600
1244
1.4473
1104
1.4296
211
1.4162
20
1.3162
1
1.3491
9
1.3715
14
1.2419
2
1.4627
38
1.4550
155
1.4430
153
MP2=FULL 1.4832
1280
1.4673
1625
1.4690
1441
1.4679
1539
1.4603
2219
1.4533
1686
1.4540
1727
1.4603
2106
1.4540
1230
1.4449
1299
1.4283
331
1.4219
8
1.4408
923
1.4603
1516
1.4441
1548
1.4199
233
1.4579
825
1.4342
811
1.4209
221
1.4148
21
1.3096
1
1.3480
9
1.3685
14
1.2394
2
1.4611
38
1.4535
155
1.4199
148
ROMP2 1.4721
81
1.4526
77
1.4533
75
1.4612
73
1.4334
81
1.4311
79
1.4325
81
1.4360
81
1.4363
81
1.4323
80
1.3912
27
  1.4202
64
1.4432
81
1.4293
75
1.4142
12
1.4387
78
1.3624
10
1.4137
12
  1.3162
1
    1.2791
1
  1.4156
20
1.3934
14
MP3 1.4408
10
1.4332
10
1.4332
10
1.4351
10
1.4622
1996
1.4172
10
1.4777
2276
1.4300
11
1.4211
10
1.4168
10
1.4286
219
1.4251
8
1.4393
533
1.4515
533
1.4386
492
1.3490
3
1.4308
10
1.4160
10
1.1968
1
1.4750
6
1.3099
1
1.3415
1
1.3908
4
1.2285
2
1.3602
2
1.4453
94
1.3518
41
MP3=FULL   1.4425
313
1.4414
306
1.4434
306
1.4767
2228
1.4259
305
1.4757
2097
1.4289
305
1.4302
311
1.4220
305
1.4083
180
  1.4339
480
1.4447
473
1.4256
438
  1.4386
293
1.3896
174
  1.4577
5
1.3033
1
1.3406
1
1.3452
3
1.2263
2
1.3589
2
1.4146
67
1.3512
38
MP4 1.4163
29
1.4628
766
1.4766
22
1.5006
53
1.4456
816
1.4317
11
1.4339
11
1.4057
15
1.4396
621
1.3685
20
1.4222
161
1.4314
8
1.4346
474
1.4468
490
1.4253
392
1.3573
3
1.4431
407
1.4042
219
1.3577
3
1.4612
4
1.3209
1
1.3494
1
1.4404
4
1.2460
2
1.3677
2
1.4231
68
1.4026
61
MP4=FULL 1.4430
10
1.4606
540
1.4394
10
1.4403
10
1.4432
558
1.4209
10
1.4236
10
1.4249
10
1.4416
498
1.4177
10
1.4237
158
1.4277
8
1.4296
9
1.4471
502
1.4213
313
1.3541
3
1.4427
376
1.4044
213
1.3543
3
1.4404
3
1.3139
1
1.3484
1
1.3582
4
1.2438
2
1.3663
2
1.4259
69
1.3669
44
B2PLYP 1.4707
806
1.4513
806
1.4521
805
1.4525
805
1.4788
2143
1.4459
714
1.4472
728
1.4461
709
1.4458
709
1.4456
812
1.4363
317
1.3278
1
1.4425
713
1.4499
714
1.4706
2044
1.3266
1
1.4467
633
1.4411
695
1.3764
3
1.4732
6
1.3089
1
1.3365
1
1.3851
5
1.2321
2
1.3579
2
1.4485
157
1.4344
139
B2PLYP=FULL 1.4720
713
1.4536
733
1.4534
712
1.4535
712
1.4466
731
1.4452
711
1.4470
731
1.4450
712
1.4447
712
1.4432
704
1.4355
314
  1.4421
711
1.4497
705
1.4417
681
  1.4461
631
1.4338
594
  1.4714
6
1.3071
1
1.3362
1
1.3843
5
1.3295
3
1.3575
2
1.4480
157
1.4382
156
B2PLYP=FULLultrafine 1.4677
488
1.4480
487
1.4491
486
1.4490
486
1.4845
2405
1.4413
479
1.4418
485
1.4410
480
1.4401
486
1.4385
484
1.4356
315
  1.4377
485
1.4868
1637
1.4774
1645
  1.4460
442
1.4791
1586
  1.4714
6
1.4646
7
  1.3988
4
1.3553
5
1.3575
2
1.4480
157
1.4420
152
Configuration interaction CID 1.3986
23
1.4563
1258
1.4584
1188
1.4590
1189
1.4541
1625
1.4530
36
1.4540
20
1.4478
1137
1.4179
35
1.3552
20
1.4236
232
1.4180
8
1.4207
9
1.4329
226
1.4164
215
1.3436
3
1.4243
10
1.4100
10
1.1917
1
1.4681
6
1.3013
1
1.3356
1
1.3844
4
1.2212
2
1.3519
2
1.4328
110
1.3491
46
CISD 1.4084
24
1.4572
1242
1.4591
1188
1.4594
1189
1.4609
1588
1.4885
26
1.4468
18
1.4481
1147
1.4185
35
1.3647
19
1.4233
227
1.4187
8
1.4217
9
1.4343
225
1.4189
226
1.3446
3
1.4251
10
1.4108
10
1.1932
1
1.4685
6
1.3020
1
1.3369
1
1.3851
4
1.2224
2
1.3523
2
1.4251
104
1.3531
50
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 cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Quadratic configuration interaction QCISD 1.4593
122
1.4860
1831
1.4767
1251
1.4737
1282
1.4614
1497
1.4532
1284
1.4549
1133
1.4599
1287
1.4551
1149
1.4486
973
1.4322
247
1.4265
8
1.4449
802
1.4628
1149
1.4415
799
1.3541
4
1.4521
611
1.4255
444
1.2817
2
1.4758
6
1.3117
1
1.3451
1
1.3873
5
1.2333
2
1.3626
2
1.4448
113
1.3740
62
QCISD(T) 1.4481
10
1.4648
13
1.4526
11
1.4517
11
1.4428
786
1.4335
11
1.4070
17
1.4352
334
1.3941
26
1.4235
10
1.4279
186
1.4310
8
1.4321
514
1.4460
621
1.4238
417
1.3560
3
1.4386
447
1.4064
267
1.3565
3
1.4660
4
1.3179
1
1.3503
1
1.3917
5
1.2409
2
1.3666
2
1.4250
81
1.3731
55
QCISD(T)=FULL         1.4356
409
  1.4341
396
1.5228
1
    1.4186
167
    1.4426
391
1.3990
242
1.3545
67
1.4379
325
1.3934
156
1.3045
54
1.4599
4
1.3110
1
  1.3636
3
1.2385
2
1.3653
2
1.4152
70
1.3568
48
QCISD(TQ) 1.4488
10
1.4425
10
1.4295
9
1.4317
9
1.3783
47
1.4245
10
1.3298
36
1.4163
9
1.4285
10
1.4240
8
1.3597
15
1.4337
2
1.4839
6
1.3737
40
1.2902
25
1.2916
11
1.3311
36
1.3026
15
1.2888
3
            1.2744
1
1.2551
1
QCISD(TQ)=FULL         1.3106
27
  1.3422
19
      1.2992
8
    1.3213
29
1.2459
18
1.2766
6
1.2898
25
1.3026
11
1.3088
3
            1.2735
1
1.2510
1
Coupled Cluster CCD 1.4583
117
1.4716
1280
1.4732
1216
1.4713
1264
1.4634
1750
1.4537
1211
1.4544
1101
1.4564
1203
1.4476
959
1.4426
897
1.4304
239
1.4249
8
1.4417
806
1.4620
1127
1.4365
728
1.3523
4
1.4477
630
1.4180
388
1.2797
2
1.4750
6
1.3098
1
1.3985
5
1.3920
9
1.2302
2
1.3612
2
1.4449
112
1.3541
48
CCSD 1.4477
10
1.4609
13
1.4485
11
1.4484
11
1.4525
1055
1.4373
200
1.4367
204
1.4375
203
1.4349
202
1.4401
513
1.4270
231
1.4260
8
1.4515
684
1.4628
798
1.4498
697
1.3232
82
1.4482
536
1.4240
354
1.2934
24
1.4755
6
1.3109
1
1.3445
1
1.3868
5
1.2323
2
1.3621
2
1.4394
96
1.3496
40
CCSD=FULL 1.4474
10
1.4389
10
1.4389
10
1.4402
10
1.4557
779
1.4194
10
1.4217
10
1.4315
11
1.4228
10
1.4376
504
1.4233
222
1.3757
5
1.4401
664
1.4498
698
1.4238
615
1.3614
78
1.4464
504
1.4063
311
1.2836
25
1.4690
6
1.3042
1
1.3435
1
1.3470
3
1.2299
2
1.3608
2
1.4371
94
1.3443
43
CCSD(T) 1.4482
10
1.4499
14
1.4524
11
1.4516
11
1.4527
831
1.4356
350
1.4345
258
1.4386
336
1.4288
273
1.4313
242
1.4224
197
1.4307
8
1.4369
500
1.4476
627
1.4203
427
1.3413
78
1.4400
461
1.3861
236
1.3128
61
1.4748
5
1.3176
1
1.3511
10
1.3467
13
1.2404
2
1.3664
2
1.4167
78
1.3698
58
CCSD(T)=FULL 1.4479
10
1.4423
10
1.4423
10
1.4432
10
1.4390
644
1.4228
10
1.4253
10
1.4446
9
1.4268
10
1.4193
10
1.4174
169
1.4270
8
1.4354
512
1.4497
576
1.4147
373
1.3455
83
1.4412
404
1.3961
212
1.3110
58
1.4596
4
1.3107
1
1.3500
10
1.3399
13
1.2891
3
1.3648
2
1.4201
76
1.3606
57
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 cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD cc-pVTZ-PP aug-cc-pVTZ-PP Def2TZVPP
hartree fock HF 1.4766
2294
1.4725
2254
1.4691
2300
1.4633
2267
1.4636
2296
1.4635
2300
1.4449
6
  1.4621
2654
ROHF 1.4195
2
1.4140
2
1.4099
2
1.4001
2
1.4037
2
1.4034
2
    1.3951
27
density functional LSDA 1.4554
10
1.4478
10
1.4423
10
1.4313
10
1.4282
10
1.4280
10
1.4346
6
  1.4057
41
BLYP 1.4654
10
1.4571
10
1.4536
10
1.4420
10
1.4488
10
1.4491
10
1.4565
6
  1.4458
259
B1B95 1.4883
1206
1.4827
1206
1.4697
44
1.4711
38
1.4630
44
1.4630
44
1.4425
6
  1.4283
260
B3LYP 1.4884
2289
1.4820
2249
1.4797
2285
1.4724
2242
1.4728
2278
1.4733
2264
1.4480
6
  1.4703
2560
B3LYPultrafine 1.4867
13
1.4778
13
1.4761
13
1.4651
13
1.4702
13
1.4704
13
1.4480
6
  1.4354
260
B3PW91 1.4511
10
1.4437
10
1.4386
10
1.4278
10
1.4336
10
1.4337
10
1.4461
6
  1.4328
260
mPW1PW91 1.4487
10
1.4413
10
1.4361
10
1.4255
10
1.4313
10
1.4314
10
1.4443
6
  1.4308
260
M06-2X 1.4480
10
1.4418
10
1.4336
10
1.4236
10
1.4318
10
1.4317
10
1.4469
6
  1.4323
257
PBEPBE 1.4587
10
1.4511
10
1.4461
10
1.4354
10
1.4420
10
1.4423
10
1.4526
6
  1.4740
2636
PBEPBEultrafine 1.4587
10
1.4511
10
1.4461
10
1.4354
10
1.4420
10
1.4423
10
1.4526
6
  1.4407
259
PBE1PBE 1.4485
10
1.4412
10
1.4359
10
1.4255
10
1.4313
10
1.4313
10
1.4448
6
  1.4310
260
HSEh1PBE 1.4489
10
1.4417
10
1.4365
10
1.4261
10
1.4313
10
1.4313
10
1.4443
6
  1.4307
260
TPSSh             1.4505
6
  1.4366
260
wB97X-D 1.4667
475
1.4568
477
1.4516
490
1.4478
462
1.4463
490
1.4463
490
1.4479
6
  1.4324
260
B97D3             1.4516
6
  1.4404
260
Moller Plesset perturbation MP2 1.5064
2205
1.4835
2163
1.4953
2171
1.4726
2132
1.4912
2194
1.4909
2197
1.4528
6
  1.4685
2556
MP2=FULL 1.4725
10
1.4494
10
1.4565
10
1.4316
10
1.4543
10
1.4539
10
1.4468
6
  1.4347
258
ROMP2 1.4359
2
1.4163
2
1.4212
2
1.3994
2
1.4180
2
1.4176
2
    1.4123
28
MP3 1.4719
10
1.4502
10
1.4556
10
1.4320
10
1.4530
10
1.4526
10
1.4515
6
  1.4297
175
MP3=FULL             1.4154
2
  1.4054
145
MP4 1.4763
10
1.4546
10
1.4607
10
1.4370
10
1.4578
10
1.4574
10
1.4310
4
  1.4081
110
MP4=FULL 1.4763
10
1.4546
10
1.4607
10
1.4370
10
1.4575
10
1.4571
10
1.4249
4
  1.4128
125
B2PLYP 1.4071
3
1.3972
3
1.3923
3
1.3786
3
1.3874
3
1.3873
3
1.4501
6
  1.4360
260
B2PLYP=FULL             1.4483
6
  1.4352
260
B2PLYP=FULLultrafine             1.4483
6
  1.4352
260
Configuration interaction CID 1.4664
10
1.4451
10
1.4504
10
1.4270
10
1.4477
10
1.4473
10
1.4438
6
  1.4179
196
CISD 1.4674
10
1.4460
10
1.4514
10
1.4280
10
1.4488
10
1.4483
10
1.4441
6
  1.4168
195
Quadratic configuration interaction QCISD 1.4774
10
1.4539
10
1.4612
10
1.4359
10
1.4585
10
1.4581
10
1.4528
6
  1.4335
205
QCISD(T) 1.4801
10
1.4571
10
1.4641
10
1.4394
10
1.4612
10
1.4608
10
1.4566
6
  1.4164
160
QCISD(T)=FULL             1.4503
6
  1.4083
143
QCISD(TQ) 1.4807
10
1.4575
10
1.4644
10
1.4395
10
1.4617
10
1.4612
10
    1.2919
4
QCISD(TQ)=FULL                 1.2809
3
Coupled Cluster CCD 1.4745
10
1.4511
10
1.4582
10
1.4329
10
1.4555
10
1.4550
10
1.4520
6
  1.4298
195
CCSD 1.4772
10
1.4535
10
1.4608
10
1.4354
10
1.4582
10
1.4577
10
1.4525
6
  1.4268
192
CCSD=FULL 1.4772
10
1.4535
10
1.4608
10
1.4354
10
1.4579
10
1.4573
10
1.4463
6
  1.4209
190
CCSD(T) 1.4801
10
1.4570
10
1.4640
10
1.4391
10
1.4611
10
1.4607
10
1.4564
6
  1.4193
155
CCSD(T)=FULL 1.4801
10
1.4570
10
1.4640
10
1.4391
10
1.4608
10
1.4603
10
1.4501
6
  1.4111
147
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.