National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 18October 2016
NIST Standard Reference Database 101
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III.G.1.a.

Comparison of levels of theory for N-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 1.3401
205
PM3 1.3574
206
PM6 1.3597
411
composite G2 1.3556
355
G3 1.3485
376
G3B3 1.3461
424
G3MP2 1.1826
10
G4 1.3381
420
CBS-Q 1.3248
294
molecular mechanics DREIDING 1.4603
6

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 cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ
hartree fock HF 1.3664
390
1.3374
415
1.3372
390
1.3336
392
1.3263
441
1.3253
390
1.3150
250
1.3243
389
1.3257
392
1.3233
394
1.3442
201
1.3096
5
1.3245
435
1.3285
386
1.3220
379
1.2807
98
1.3285
361
1.3221
355
1.2812
79
1.2198
5
1.2242
2
1.1639
9
  1.4140
8
ROHF 1.3097
8
1.2814
31
1.2636
27
1.2665
27
1.2626
30
1.2508
27
1.2486
27
1.2444
27
1.2640
31
1.2576
9
1.1432
1
  1.2527
21
1.2560
26
1.2461
26
1.2594
16
1.2686
28
1.2606
28
1.2463
15
    1.1440
3
   
density functional LSDA 1.3846
394
1.3429
399
1.3433
400
1.3415
399
1.3326
398
1.3317
399
1.3311
398
1.3272
396
1.3281
398
1.3284
398
1.1688
2
  1.3192
181
1.3330
394
1.3258
393
1.3572
6
1.3322
369
1.3145
162
1.3859
4
    1.1690
6
   
SVWN   1.3451
410
    1.3371
399
1.3246
182
1.3358
406
1.3199
182
1.3206
183
1.3211
184
1.1688
2
  1.3622
276
1.3273
179
1.3199
179
  1.3242
154
1.3162
153
      1.1690
6
   
BLYP 1.4149
384
1.3675
386
1.3660
309
1.3639
385
1.3570
465
1.3545
384
1.3547
381
1.3488
310
1.3527
384
1.3520
383
1.1781
2
  1.3387
176
1.3566
377
1.3493
380
  1.3730
212
1.3470
71
      1.1780
6
   
B1B95 1.3892
411
1.3514
412
1.3515
412
1.3485
412
1.3376
391
1.3386
413
1.3393
405
1.3352
412
1.3356
415
1.3372
406
1.2871
1
  1.3243
188
1.3401
408
1.3332
408
1.2909
10
1.3447
369
1.3272
231
1.2725
9
    1.1663
5
   
B3LYP 1.3980
393
1.3552
413
1.3548
388
1.3516
392
1.3443
413
1.3428
393
1.3438
413
1.3389
384
1.3326
255
1.3392
427
1.3740
158
1.3214
5
1.3384
434
1.3456
390
1.3384
378
1.2975
80
1.3396
251
1.3397
413
1.2906
76
1.2448
5
  1.1672
6
  1.4252
8
B3LYPultrafine   1.3373
99
    1.3451
386
1.3250
95
1.3306
130
1.3218
95
    1.1673
2
1.3228
3
1.3169
124
1.3379
153
1.3394
231
  1.3315
145
1.3319
397
      1.1672
6
   
B3PW91 1.3801
247
1.3494
383
1.3497
382
1.3458
385
1.3374
379
1.3368
383
1.3350
310
1.3351
380
1.3258
249
1.3353
383
1.1676
2
  1.3242
182
1.3387
380
1.3319
378
  1.3550
211
1.3406
84
      1.1677
6
   
mPW1PW91 1.3778
260
1.3462
382
1.3432
262
1.3440
389
1.3343
377
1.3363
382
1.3337
382
1.3305
382
1.3328
386
1.3326
383
1.1657
2
  1.3206
180
1.3364
377
1.3258
277
  1.3384
307
1.3168
156
      1.1658
6
   
M06-2X 1.3730
191
1.3442
191
1.3364
343
1.3398
191
1.3408
415
1.3305
189
1.3308
189
1.3279
189
1.3280
191
1.3278
212
1.1633
2
  1.3260
186
1.3326
187
1.3277
208
  1.3311
161
1.3255
181
      1.1637
6
   
PBEPBE 1.3923
248
1.3603
384
1.3527
246
1.3493
248
1.3479
379
1.3474
379
1.3475
382
1.3447
381
1.3461
386
1.3532
379
1.3857
153
1.3282
5
1.3341
180
1.3484
367
1.3431
376
1.3200
9
1.3370
166
1.3325
191
1.3015
8
1.1682
1
  1.1789
6
  1.4277
8
PBEPBEultrafine   1.3457
99
    1.3524
321
1.3324
95
1.3331
101
1.3291
95
    1.1789
2
1.3291
3
1.3250
124
1.3449
153
1.3390
153
  1.3388
145
1.3319
147
      1.1789
6
   
PBE1PBE 1.3726
172
1.3387
172
1.3387
172
1.3353
173
1.3345
407
1.3253
171
1.3251
171
1.3218
171
1.3220
173
1.3224
173
1.1667
2
  1.3193
169
1.3271
169
1.3214
169
  1.3258
151
1.3190
150
      1.1686
6
   
HSEh1PBE 1.3783
190
1.3744
418
1.3432
190
1.3403
191
1.3391
408
1.3299
189
1.3397
417
1.3270
189
1.3271
191
1.3273
191
1.1664
2
  1.3253
186
1.3321
187
1.3596
415
  1.3308
161
1.3240
160
      1.1665
6
   
TPSSh 1.4028
34
1.3524
142
1.3525
142
1.3472
143
1.3451
435
1.3354
141
1.3453
435
1.3323
141
1.3555
34
1.3707
395
1.1719
2
  1.3266
130
1.3381
139
1.3405
433
1.2050
5
1.3302
131
1.3295
136
1.2050
5
    1.1718
6
   
wB97X-D 1.3975
59
1.3613
59
1.3615
463
1.3571
59
1.3509
458
1.3497
57
1.3407
458
1.3472
57
1.3481
463
1.3465
59
1.1651
2
  1.3359
458
1.3414
456
1.3465
459
1.3036
11
1.3560
55
1.3460
457
1.3036
11
         
B97D3 1.3216
6
1.3694
428
1.2953
6
1.3039
6
1.3594
425
1.2732
4
1.2754
4
1.2682
4
1.3557
428
1.2904
6
1.1763
2
  1.2668
4
1.3598
2
1.3560
2
  1.3612
2
1.3540
419
           
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 cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 1.3924
255
1.3684
415
1.3671
387
1.3662
390
1.3683
450
1.3454
390
1.3484
413
1.3700
441
1.3454
389
1.3370
336
1.1846
2
1.3234
2
1.3412
435
1.3517
389
1.3351
319
1.2857
54
1.3473
249
1.3302
220
1.2676
52
1.3028
3
1.2152
3
1.1892
10
  1.4294
8
MP2=FULL 1.3891
251
1.3632
288
1.3626
270
1.3611
271
1.3536
393
1.3407
311
1.3429
316
1.3420
386
1.3343
252
1.3286
269
1.1821
2
  1.3326
188
1.3467
285
1.3301
288
1.2821
56
1.3404
192
1.3277
192
1.2791
52
1.2442
5
1.2144
3
1.1870
10
1.1856
2
1.4278
8
ROMP2 1.3334
28
1.3006
28
1.3006
28
1.3060
28
1.2811
28
1.2809
28
1.2797
28
1.2746
28
1.2747
28
1.2783
27
1.1827
1
  1.2887
23
1.2917
26
1.2752
23
1.1695
1
1.2917
26
1.1710
1
1.1680
1
    1.1830
4
   
MP3         1.3400
379
  1.3372
424
      1.1662
2
  1.3094
118
1.3215
116
1.3105
116
            1.1661
6
   
MP3=FULL   1.3722
59
1.3725
59
1.3695
59
1.3402
431
1.3509
57
1.3363
395
1.3497
57
1.3499
59
1.3437
59
1.1641
2
  1.3163
124
1.3281
122
1.3121
120
  1.3598
53
1.3639
43
      1.1641
6
   
MP4 1.3376
6
1.3543
215
1.3825
4
1.3388
3
1.3375
225
    1.2669
4
1.3304
199
1.2519
4
1.1882
2
  1.3305
139
1.3376
136
1.3041
149
  1.3383
131
1.3146
104
      1.1876
6
   
MP4=FULL   1.3581
148
    1.3254
131
      1.3278
139
  1.1859
2
    1.3395
142
1.3186
122
  1.3363
132
1.3139
100
      1.1857
6
   
B2PLYP 1.3899
130
1.3539
131
1.3540
131
1.3522
131
1.3471
361
1.3377
129
1.3394
130
1.3354
129
1.3366
132
1.3342
155
1.1742
2
  1.3336
129
1.3418
127
1.3403
359
  1.3413
125
1.3325
148
      1.1738
6
   
B2PLYP=FULL 1.3886
131
1.3542
132
1.3539
131
1.3521
131
1.3384
130
1.3373
129
1.3387
130
1.3350
129
1.3352
131
1.3331
131
1.1736
2
  1.3333
129
1.3415
127
1.3311
125
  1.3409
125
1.3303
122
      1.1732
6
   
B2PLYP=FULLultrafine 1.4052
61
1.3717
61
1.3718
61
1.3679
61
1.3620
232
1.3551
59
1.3558
59
1.3536
59
1.3531
61
1.3504
61
1.1736
2
  1.3520
59
1.3625
57
1.3555
57
  1.3632
57
1.3555
57
           
Configuration interaction CID 1.3923
2
1.3421
253
1.3435
253
1.3419
254
1.3301
307
1.3529
5
1.3535
5
1.3234
247
1.2615
8
1.2308
4
1.1599
2
    1.3565
5
              1.1632
6
   
CISD 1.4384
4
1.3458
258
1.3453
253
1.3436
254
1.3296
301
1.3990
9
1.3541
5
1.3237
247
1.2623
8
1.2315
4
1.1610
2
    1.3570
5
              1.1650
6
   
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 cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ
Quadratic configuration interaction QCISD 1.2957
16
1.3701
333
1.3582
250
1.3551
254
1.3438
289
1.3310
247
1.3318
246
1.3350
269
1.3293
262
1.3246
224
1.1736
2
  1.3311
182
1.3390
246
1.3220
206
  1.3394
155
1.3246
150
  1.1584
1
  1.1740
7
   
QCISD(T)         1.3297
213
  1.3099
2
1.3465
57
1.2912
5
  1.1802
2
  1.3313
155
1.3312
155
1.3181
138
  1.3406
134
1.3297
99
      1.1798
6
   
QCISD(T)=FULL         1.3261
91
  1.3209
83
      1.1779
2
    1.3268
79
1.3062
71
1.2345
18
1.3218
76
1.2986
49
1.2188
15
    1.1784
7
   
QCISD(TQ)         1.2660
25
  1.2620
24
      1.1785
2
    1.2770
21
1.2238
17
1.1803
3
1.2644
17
1.1950
6
1.1810
2
         
QCISD(TQ)=FULL         1.2658
25
  1.2538
20
            1.2829
22
1.2474
11
1.1772
2
1.2384
19
1.1958
5
1.1784
1
         
Coupled Cluster CCD 1.2933
16
1.3525
246
1.3576
247
1.3544
249
1.3487
327
1.3308
240
1.3329
237
1.3327
247
1.3285
208
1.3219
205
1.1700
2
  1.3310
176
1.3368
236
1.3182
181
  1.3298
144
1.3211
125
      1.1703
7
1.1744
1
 
CCSD         1.3358
226
  1.3315
2
1.2028
3
1.3028
1
1.3296
101
1.1722
2
  1.3249
140
1.3319
162
1.3228
175
1.2447
29
1.3340
123
1.3207
119
1.2188
19
    1.1725
7
   
CCSD=FULL         1.3372
173
    1.1738
1
  1.3238
102
1.1699
2
  1.3299
146
1.3414
147
1.3189
159
1.2397
29
1.3435
136
1.3166
119
1.2182
17
    1.1705
7
1.1739
2
 
CCSD(T)   1.1780
2
    1.3284
215
1.3531
66
1.2533
9
1.3477
59
1.2767
13
1.2973
6
1.1775
3
  1.3264
149
1.3313
169
1.3132
156
1.2487
36
1.3368
152
1.3230
109
1.2482
30
1.1658
1
1.2255
3
1.1892
10
   
CCSD(T)=FULL         1.3209
163
          1.1773
2
  1.3300
150
1.3269
155
1.3109
135
1.2455
34
1.3377
129
1.3173
92
1.2253
26
  1.2247
3
1.1849
11
1.1787
4
 
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 cc-pCVDZ cc-pCVTZ aug-cc-pCVTZ Sadlej_pVTZ

average calculated bond lengths (Å)
Methods with effective core potentials (select basis sets)
CEP-31G CEP-31G* CEP-121G CEP-121G* LANL2DZ SDD
hartree fock HF 1.3502
390
1.3401
386
1.3466
390
1.3344
386
1.3419
390
1.3419
390
ROHF 1.1703
1
  1.1645
1
  1.1621
1
1.1615
1
density functional B1B95 1.3903
198
1.3816
192
1.4393
5
1.4315
5
1.4363
5
1.4363
5
B3LYP 1.3704
388
1.3590
384
1.3659
389
1.3528
385
1.3605
388
1.3609
384
B3LYPultrafine 1.5066
6
1.4859
6
1.5020
6
1.4829
6
1.4942
6
1.4942
6
wB97X-D 1.3743
59
1.3704
57
1.3693
59
1.3651
57
1.3640
59
1.3642
59
Moller Plesset perturbation MP2 1.3902
389
1.3634
385
1.3824
390
1.3574
385
1.3800
390
1.3799
390
ROMP2 1.2362
1
  1.2246
1
  1.2224
1
1.2224
1
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.