National Institute of Standards and Technology
Computational Chemistry Comparison and Benchmark DataBase
Release 17bSeptember 2015
NIST Standard Reference Database 101
IIntroduction
IIExperimental data
IIICalculated data
IVData comparisons
VCost comparisons
VIInput and output files
VIITutorials and Units
VIIILinks to other sites
IXFeedback
XOlder CCCBDB versions
XIIGeometries
XIII Vibrations
XIVReaction data
XVEntropy data
XVIBibliographic data
XVIIIon data
XVIIIBad calculations
XIXIndex of properties
XXH-bond dimers
XXIOddities

NIST policy on privacy, security, and accessibility.

Please rate our products
© 2013 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

Please send questions, comments, corrections, additions and suggestions to cccbdb@nist.gov.

return to home page

III.G.1.a.

Comparison of levels of theory for C-O


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 1.3216
210
PM3 1.3071
204
PM6 1.3509
498
composite G2 1.3237
449
G3 1.3277
471
G3B3 1.3226
523
G3MP2 1.2254
9
G4 1.3169
505
CBS-Q 1.3254
373
molecular mechanics DREIDING 1.2635
3

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 Sadlej_pVTZ
hartree fock HF 1.3637
475
1.3350
514
1.3367
486
1.3347
485
1.3006
557
1.3055
486
1.2905
303
1.2996
492
1.3029
475
1.3124
481
1.3071
264
1.2647
18
1.3134
545
1.3041
484
1.3003
478
1.2446
104
1.3068
457
1.3018
433
1.2335
72
1.1461
3
1.4011
2
1.3081
3
1.2535
12
ROHF 1.2797
18
1.2678
55
1.2685
55
1.2692
54
1.2397
59
1.2402
56
1.2431
56
1.2381
56
1.2382
51
1.2142
20
    1.2592
17
1.2378
56
1.2366
56
1.2041
34
1.2411
47
1.2344
46
1.1941
33
    1.1287
1
 
density functional LSDA 1.3659
491
1.3385
504
1.3386
507
1.3371
500
1.3108
496
1.3094
502
1.3125
498
1.3065
496
1.3055
499
1.3040
491
1.1608
4
1.1608
4
1.3035
144
1.3085
498
1.3056
495
1.2032
23
1.3118
467
1.2816
147
1.1907
20
       
SVWN 1.2257
4
1.3598
478
1.1874
4
1.1915
4
1.3352
473
1.3062
144
1.3380
477
1.3024
144
1.3028
144
1.3013
144
1.1608
4
1.1608
4
1.3373
424
1.3052
144
1.3023
144
1.1607
4
1.3051
126
1.2966
108
1.1609
4
       
BLYP 1.4143
473
1.3733
486
1.3600
399
1.3734
480
1.3331
578
1.3427
483
1.3467
479
1.3270
395
1.3410
470
1.3482
473
1.1728
4
1.1728
4
1.3322
141
1.3423
478
1.3389
476
1.1723
4
1.3642
223
1.3118
25
1.1726
4
       
B1B95 1.3718
473
1.3474
486
1.3478
484
1.3457
484
1.3178
469
1.3164
484
1.3188
491
1.3131
480
1.3140
479
1.3085
464
1.1558
4
1.1559
4
1.3035
144
1.3152
480
1.3121
477
1.1982
25
1.3118
433
1.2987
255
1.1988
24
  1.4169
2
1.4148
2
 
B3LYP 1.3942
481
1.3559
516
1.3586
486
1.3579
484
1.3195
515
1.3282
483
1.3296
511
1.3208
495
1.3108
288
1.3171
527
1.3665
194
1.2879
18
1.3343
542
1.3267
474
1.3242
471
1.2549
83
1.3101
324
1.3252
503
1.2549
72
1.1700
3
1.4298
2
1.3385
3
1.2772
12
B3LYPultrafine 1.2870
7
1.3337
78
1.1866
4
1.1909
4
1.3237
461
1.3032
60
1.3139
108
1.3009
60
1.1619
4
1.1641
4
1.1603
4
1.2726
16
1.3080
77
1.3109
121
1.3126
217
1.1598
4
1.3097
109
1.3138
472
1.1600
4
    1.1614
1
 
B3PW91 1.3691
288
1.3543
491
1.3548
488
1.3532
486
1.3193
480
1.3233
487
1.3138
400
1.3197
487
1.3056
284
1.3289
474
1.1591
4
1.1591
4
1.3087
144
1.3226
486
1.3195
484
1.1587
4
1.3418
224
1.2991
64
1.1589
4
       
mPW1PW91 1.3645
288
1.3506
481
1.3364
322
1.3489
478
1.3156
479
1.3196
482
1.3215
481
1.3159
482
1.3172
471
1.3256
473
1.1567
4
1.1567
4
1.3052
144
1.3177
475
1.2996
348
1.1563
4
1.3252
344
1.2929
129
1.1565
4
       
M06-2X 1.3636
157
1.3369
156
1.3125
424
1.3323
157
1.3338
484
1.3062
157
1.3082
157
1.3035
157
1.3037
157
1.3004
192
1.1554
4
1.1553
4
1.3054
144
1.3051
157
1.3021
192
1.1552
4
1.3070
132
1.2975
152
1.1554
4
       
PBEPBE 1.3801
291
1.3755
488
1.3515
294
1.3517
289
1.3416
483
1.3454
476
1.3473
488
1.3418
480
1.3330
471
1.3316
459
1.3755
199
1.4636
18
1.3220
144
1.3437
469
1.3442
474
1.2162
25
1.3188
158
1.3111
188
1.2027
24
1.1694
1
    1.2854
12
PBEPBEultrafine 1.2349
4
1.3441
72
1.1987
4
1.2022
4
1.3574
376
1.3119
60
1.3200
78
1.3097
60
1.1727
4
1.1752
4
1.1712
4
1.2820
16
1.3173
77
1.3193
121
1.3178
121
1.1708
4
1.3190
109
1.3128
113
1.1711
4
       
PBE1PBE 1.3725
138
1.3367
138
1.3367
138
1.3357
138
1.3332
485
1.3078
138
1.3102
138
1.3043
138
1.3048
138
1.3036
138
1.1575
4
1.1575
4
1.3056
138
1.3065
138
1.3046
138
1.1571
4
1.3059
120
1.2970
104
1.1573
4
       
HSEh1PBE 1.3706
157
1.3651
485
1.3355
157
1.3346
157
1.3361
475
1.3066
157
1.3383
490
1.3033
157
1.3038
157
1.3024
157
1.1573
4
1.1573
4
1.3055
144
1.3055
157
1.3352
485
1.1568
4
1.3072
132
1.2980
117
1.1570
4
       
TPSSh 1.3876
7
1.3541
77
1.3546
77
1.3524
77
1.3249
532
1.3214
77
1.3255
534
1.3178
77
1.3174
7
1.3244
509
    1.3190
73
1.3208
77
1.3204
534
  1.3198
70
1.3135
64
      1.1636
1
 
wB97X-D 1.3508
17
1.3178
17
1.3430
591
1.3180
17
1.3194
594
1.2917
17
1.2922
17
1.2871
17
1.3161
595
1.2878
17
    1.2870
17
1.2912
17
1.3152
595
1.2540
2
1.2925
17
1.3153
587
1.2545
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 cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 1.3734
289
1.3700
516
1.3722
481
1.3769
482
1.3351
571
1.3330
486
1.3364
512
1.3289
568
1.3260
474
1.3210
388
1.1695
4
1.2564
17
1.3353
543
1.3299
486
1.3162
409
1.2567
46
1.3200
303
1.3199
265
1.2618
39
1.1810
3
1.2662
10
1.2435
7
1.2860
12
MP2=FULL 1.3684
285
1.3528
351
1.3534
322
1.3580
320
1.3362
499
1.3198
390
1.3242
397
1.3199
488
1.3100
283
1.3062
309
1.1672
4
1.1671
4
1.3087
153
1.3121
352
1.3118
369
1.2525
42
1.3094
168
1.2917
181
1.2533
38
1.1778
3
1.2653
10
1.2414
7
1.2849
12
ROMP2 1.3728
39
1.3092
37
1.3094
37
1.3105
38
1.2712
38
1.2708
38
1.2812
36
1.2692
36
1.2635
38
1.2579
38
    1.2691
16
1.2704
36
1.2672
35
1.1478
7
1.2693
36
1.2118
16
1.1914
10
       
MP3 1.2152
4
1.1837
4
1.1837
4
1.1900
4
1.3252
452
1.1682
4
1.3205
532
1.1573
4
1.1570
4
1.1580
4
1.1546
4
1.1545
4
1.2955
68
1.2983
68
1.2940
68
1.1533
4
1.1682
4
1.1575
4
1.1538
4
       
MP3=FULL   1.3286
17
1.3304
17
1.3319
17
1.3192
528
1.2945
17
1.3171
502
1.2864
17
1.2863
17
1.2829
17
    1.3034
64
1.3060
64
1.2986
64
  1.2974
17
1.2798
14
         
MP4 1.3623
11
1.3464
218
1.2844
9
1.2809
9
1.3084
251
1.1915
5
1.1932
5
1.2365
8
1.2981
180
1.2920
11
1.1753
4
1.1754
4
1.3086
98
1.3140
103
1.2923
135
1.1744
4
1.3234
87
1.3052
67
1.1751
4
    1.1669
1
 
MP4=FULL 1.2582
4
1.3563
109
1.2157
4
1.2229
4
1.3135
102
1.1876
4
1.1893
4
1.1779
4
1.3020
98
1.1739
4
1.1730
4
1.1730
4
1.1785
4
1.3109
106
1.2927
78
1.1718
4
1.3189
91
1.2990
69
1.1724
4
    1.1654
1
 
B2PLYP 1.3836
86
1.3461
85
1.3444
86
1.3480
85
1.3477
424
1.3127
86
1.3107
92
1.3092
86
1.3081
89
1.3036
123
1.1294
1
1.1294
1
1.3122
85
1.3111
86
1.3235
454
1.1286
1
1.3143
76
1.3031
107
1.1288
1
    1.1627
1
 
B2PLYP=FULL 1.3905
82
1.3412
89
1.3516
82
1.3551
81
1.3107
89
1.3188
82
1.3135
89
1.3157
82
1.3161
82
1.3124
82
    1.3176
82
1.3174
82
1.3151
82
  1.3200
73
1.3113
67
      1.1622
1
 
B2PLYP=FULLultrafine 1.3854
21
1.3667
21
1.3682
21
1.3668
21
1.3474
242
1.3286
21
1.3307
21
1.3240
21
1.3241
21
1.3224
21
    1.3252
21
1.3277
21
1.3230
21
  1.3323
21
1.3198
19
      1.1622
1
 
Configuration interaction CID 1.2771
7
1.3352
290
1.3312
275
1.3339
274
1.3042
380
1.1680
5
1.1685
5
1.2909
281
1.2546
15
1.2672
11
1.1507
4
1.1507
4
1.1542
4
1.1647
5
1.1560
5
1.1493
4
1.1643
4
1.1534
4
1.1497
4
       
CISD 1.2749
8
1.3395
291
1.3338
278
1.3359
276
1.3061
381
1.2867
6
1.1768
6
1.2918
280
1.2557
15
1.2650
10
1.1523
4
1.1523
4
1.1563
4
1.1668
5
1.1577
5
1.1509
4
1.1662
4
1.1550
4
1.1512
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 Sadlej_pVTZ
Quadratic configuration interaction QCISD 1.4262
40
1.3716
431
1.3538
292
1.3587
300
1.3164
357
1.3196
306
1.3200
307
1.3071
328
1.3142
293
1.3061
256
1.1622
4
1.1622
4
1.3139
143
1.3137
290
1.2970
233
1.1596
5
1.3150
144
1.2982
147
1.1600
5
1.1554
1
  1.1582
1
 
QCISD(T) 1.2343
4
1.2787
12
1.2688
8
1.2691
8
1.3064
238
1.2245
9
1.2832
17
1.3260
36
1.3084
18
1.2313
7
1.1679
4
1.1679
4
1.3104
109
1.2983
175
1.2896
139
1.1667
4
1.3025
116
1.2819
86
1.1673
4
    1.1647
1
 
QCISD(T)=FULL         1.3073
50
  1.3174
45
            1.3064
44
1.2981
35
1.2481
11
1.3171
38
1.2882
27
1.2385
10
    1.1632
1
 
QCISD(TQ) 1.2260
4
1.1973
4
1.1973
4
1.2041
4
1.2707
21
1.1785
4
1.2616
18
1.1684
4
1.1682
4
1.1681
4
1.1653
4
1.1653
4
1.1683
4
1.2486
18
1.2054
12
1.1648
7
1.2301
14
1.1628
9
1.1296
1
       
QCISD(TQ)=FULL         1.2763
16
  1.2271
9
            1.2729
16
1.2417
9
1.1145
1
1.2616
9
1.1481
3
         
Coupled Cluster CCD 1.4239
40
1.3484
302
1.3447
284
1.3497
293
1.3328
408
1.3110
296
1.3132
294
1.3010
289
1.3038
227
1.3014
229
1.1575
4
1.1575
4
1.3103
135
1.3081
282
1.2858
183
1.1545
5
1.2996
160
1.2721
118
1.1550
5
  1.4256
2
1.3300
3
 
CCSD 1.2233
4
1.2691
12
1.2589
8
1.2605
8
1.3102
262
1.2177
9
1.2768
17
1.2979
16
1.3896
21
1.2997
72
1.1602
4
1.1602
4
1.3032
102
1.3050
148
1.3061
173
1.2203
25
1.3128
90
1.3002
112
1.1752
12
    1.1557
1
 
CCSD=FULL 1.2232
4
1.1928
4
1.1928
4
1.2003
4
1.3061
143
1.1734
4
1.1743
4
1.1630
4
1.1627
4
1.2933
67
1.1580
4
1.1580
4
1.3015
104
1.3065
106
1.2957
134
1.2316
27
1.3157
95
1.2903
104
1.1718
14
       
CCSD(T) 1.2325
4
1.2759
16
1.2666
8
1.2672
8
1.3191
235
1.3092
43
1.2794
23
1.2819
36
1.2964
18
1.2161
9
1.2334
7
1.2335
7
1.3101
104
1.2998
169
1.2823
151
1.2362
34
1.3026
143
1.2673
89
1.2389
23
1.1622
1
1.2629
6
1.1674
5
 
CCSD(T)=FULL 1.2325
4
1.2007
4
1.2007
4
1.2073
4
1.3088
167
1.1793
4
1.1805
4
1.1694
4
1.1692
4
1.1665
4
1.1649
4
1.1648
4
1.3103
113
1.3062
130
1.2895
94
1.2452
31
1.3142
105
1.2753
68
1.2252
21
  1.2620
6
1.2409
7
 
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 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 1.3445
487
1.3173
468
1.3431
487
1.3149
471
1.3378
488
1.3374
486
density functional LSDA 1.2169
4
1.1939
4
1.2130
4
1.1858
4
1.1991
4
1.1990
4
SVWN 1.2169
4
1.1939
4
1.2130
4
1.1858
4
1.1991
4
1.1990
4
BLYP 1.2217
4
1.1968
4
1.2183
4
1.1889
4
1.2132
4
1.2135
4
B1B95 1.3699
257
1.3400
253
1.2421
6
1.2155
6
1.2377
6
1.2378
6
B3LYP 1.3716
487
1.3426
467
1.3695
484
1.3398
469
1.3620
485
1.3617
483
B3LYPultrafine 1.2081
4
1.1847
4
1.2049
4
1.1768
4
1.2083
5
1.1988
4
B3PW91 1.2051
4
1.1825
4
1.2017
4
1.1748
4
1.1961
4
1.1962
4
mPW1PW91 1.2020
4
1.1797
4
1.1987
4
1.1721
4
1.1932
4
1.1934
4
M06-2X 1.1948
4
1.1748
4
1.1905
4
1.1652
4
1.1907
4
1.1908
4
PBEPBE 1.2178
4
1.1940
4
1.2142
4
1.1864
4
1.2097
4
1.2099
4
PBEPBEultrafine 1.2178
4
1.1940
4
1.2142
4
1.1864
4
1.2097
4
1.2100
4
PBE1PBE 1.2024
4
1.1801
4
1.1990
4
1.1726
4
1.1938
4
1.1940
4
HSEh1PBE 1.2030
4
1.1806
4
1.1998
4
1.1731
4
1.1939
4
1.1941
4
wB97X-D 1.3335
17
1.3037
17
1.3307
17
1.3002
17
1.3232
17
1.3232
17
Moller Plesset perturbation MP2 1.3940
492
1.3480
468
1.3862
490
1.3450
470
1.3831
494
1.3827
492
MP2=FULL 1.2320
4
1.1971
4
1.2256
4
1.1895
4
1.2210
4
1.2209
4
MP3 1.2110
4
1.1828
4
1.2033
4
1.1744
4
1.1983
4
1.1981
4
MP4 1.2440
4
1.2019
4
1.2388
4
1.1956
4
1.2331
4
1.2333
4
MP4=FULL 1.2440
4
1.2019
4
1.2388
4
1.1956
4
1.2330
4
1.2330
4
B2PLYP 1.1842
1
1.1578
1
1.1781
1
1.1475
1
1.1759
1
1.1760
1
Configuration interaction CID 1.2095
4
1.1791
4
1.2025
4
1.1706
4
1.1977
4
1.1975
4
CISD 1.2130
4
1.1811
4
1.2058
4
1.1726
4
1.2009
4
1.2007
4
Quadratic configuration interaction QCISD 1.2254
4
1.1912
4
1.2183
4
1.1833
4
1.2133
4
1.2131
4
QCISD(T) 1.2293
4
1.1951
4
1.2227
4
1.1878
4
1.2171
4
1.2170
4
QCISD(TQ) 1.2246
4
1.1928
4
1.2176
4
1.1851
4
1.2125
4
1.2123
4
Coupled Cluster CCD 1.2170
4
1.1857
4
1.2100
4
1.1777
4
1.2051
4
1.2049
4
CCSD 1.2213
4
1.1887
4
1.2142
4
1.1807
4
1.2093
4
1.2091
4
CCSD=FULL 1.2213
4
1.1887
4
1.2142
4
1.1807
4
1.2091
4
1.2088
4
CCSD(T) 1.2282
4
1.1943
4
1.2215
4
1.1868
4
1.2160
4
1.2159
4
CCSD(T)=FULL 1.2282
4
1.1943
4
1.2215
4
1.1868
4
1.2159
4
1.2156
4
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.