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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 1.3263
250
PM3 1.3173
243
PM6 1.3503
524
composite G2 1.3258
472
G3 1.3271
492
G3B3 1.3267
542
G3MP2 1.2330
19
G4 1.3196
526
CBS-Q 1.3246
394
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 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 daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
hartree fock HF 1.3627
500
1.3387
539
1.3406
511
1.3456
510
1.3022
588
1.3076
511
1.2970
337
1.3018
517
1.3047
503
1.3134
510
1.3094
274
1.2647
18
1.3123
572
1.3039
620
1.3063
509
1.3025
503
1.2655
117
1.3088
481
1.3038
456
1.2617
89
1.1461
3
1.2807
4
1.2456
5
1.1931
7
1.1769
8
1.2535
12
ROHF 1.3441
11
1.2912
58
1.2919
58
1.2915
57
1.2566
58
1.2587
59
1.2603
59
1.2565
59
1.2584
54
1.2666
13
1.2181
7
  1.2602
27
1.2281
5
1.2562
59
1.2551
59
1.2333
38
1.2599
50
1.2533
49
1.2203
37
  1.1596
2
1.1435
3
1.2124
5
1.2066
5
 
density functional LSDA 1.3692
271
1.3384
350
1.3433
280
1.3420
281
1.3124
355
1.3109
359
1.3146
355
1.3081
356
1.3069
356
1.3043
352
1.3746
14
1.1608
4
1.3167
118
1.2255
1
1.3097
356
1.3074
352
1.2109
16
1.3118
327
1.2961
167
1.1933
13
  1.1364
1
1.1271
1
1.1589
4
1.1502
4
 
BLYP 1.4146
500
1.3749
511
1.3627
424
1.3754
505
1.3341
600
1.3447
508
1.3485
505
1.3301
420
1.3423
499
1.3491
502
1.3719
19
1.1728
4
1.3353
188
1.2965
6
1.3443
503
1.3409
501
1.1723
4
1.3590
262
1.3268
75
1.1726
4
  1.1990
2
1.1864
2
1.2234
8
1.2159
8
 
B1B95 1.3733
499
1.3530
466
1.3497
507
1.3478
507
1.3200
492
1.3185
507
1.3206
516
1.3152
503
1.3155
506
1.3104
491
1.3463
19
1.1559
4
1.3074
191
1.2733
6
1.3174
503
1.3142
500
1.2078
22
1.3142
455
1.3033
287
1.2088
21
  1.2983
4
1.2920
4
1.1816
6
1.2054
7
 
B3LYP 1.3947
509
1.3571
541
1.3601
512
1.3597
510
1.3225
542
1.3300
509
1.3313
538
1.3227
521
1.3153
329
1.3218
544
1.3690
202
1.2879
18
1.3345
570
1.3238
619
1.3286
500
1.3268
499
1.2805
96
1.3145
351
1.3273
528
1.2819
89
1.1700
3
1.3073
4
1.2725
5
1.2083
8
1.2011
8
1.2772
12
B3LYPultrafine 1.2870
7
1.3410
129
1.1866
4
1.1909
4
1.3254
488
1.3139
111
1.3168
157
1.3099
111
1.1619
4
1.2349
10
1.3545
19
1.2726
16
1.3140
128
1.2809
6
1.3149
172
1.3132
263
1.1598
4
1.3140
159
1.3159
498
1.1600
4
  1.1848
2
1.1694
3
1.2083
8
1.2011
8
 
B3PW91 1.3723
324
1.3559
516
1.3564
513
1.3550
511
1.3214
505
1.3252
512
1.3167
426
1.3216
512
1.3104
324
1.3297
503
1.3506
19
1.1591
4
1.3124
191
1.2772
6
1.3245
511
1.3213
509
1.1587
4
1.3368
262
1.3076
110
1.1589
4
  1.1835
2
1.1726
2
1.2059
8
1.1989
8
 
mPW1PW91 1.3678
324
1.3523
506
1.3390
349
1.3508
503
1.3178
504
1.3216
507
1.3234
507
1.3178
507
1.3185
500
1.3264
502
1.3472
19
1.1567
4
1.3089
191
1.2742
6
1.3196
500
1.3038
375
1.1563
4
1.3230
383
1.2985
175
1.1565
4
  1.1807
2
1.1701
2
1.2014
8
1.1960
8
 
M06-2X 1.3639
204
1.3402
203
1.3486
621
1.3365
204
1.3329
518
1.3101
204
1.3117
204
1.3068
204
1.3071
204
1.3038
239
1.3463
19
1.1553
4
1.3089
191
1.2749
6
1.3087
204
1.3053
239
1.1552
4
1.3093
182
1.3010
201
1.1554
4
  1.1770
2
1.1682
2
1.2005
8
1.1945
8
 
PBEPBE 1.3835
327
1.3771
515
1.3565
327
1.3568
322
1.3433
508
1.3469
501
1.3487
514
1.3433
505
1.3346
499
1.3329
484
1.3781
207
1.4636
18
1.3257
191
1.3283
628
1.3452
494
1.3455
499
1.2258
22
1.3227
203
1.3152
234
1.2109
21
1.1694
1
1.1964
2
1.1847
2
1.2192
8
1.2124
8
1.2854
12
PBEPBEultrafine 1.2349
4
1.3518
123
1.1987
4
1.2022
4
1.3551
414
1.3228
111
1.3267
129
1.3191
111
1.1727
4
1.2450
10
1.3655
19
1.2820
16
1.3233
128
1.2898
6
1.3236
172
1.3216
172
1.1708
4
1.3234
159
1.3172
163
1.1711
4
  1.1964
2
1.1847
2
1.2192
8
1.2124
8
 
PBE1PBE 1.3721
185
1.3405
171
1.3406
185
1.3401
185
1.3330
515
1.3120
185
1.3139
185
1.3081
185
1.3085
185
1.3076
185
1.3473
19
1.1575
4
1.3094
185
1.2742
6
1.3105
185
1.3082
185
1.1571
4
1.3088
170
1.3012
154
1.1573
4
  1.1812
2
1.1708
2
1.2018
8
1.1965
8
 
HSEh1PBE 1.3708
204
1.3638
518
1.3393
204
1.3389
204
1.3355
507
1.3107
204
1.3377
522
1.3070
204
1.3075
204
1.3063
204
1.3474
19
1.1573
4
1.3092
191
1.2743
6
1.3094
204
1.3339
518
1.1568
4
1.3097
182
1.3020
165
1.1570
4
  1.1812
2
1.1706
2
1.2030
8
1.1964
8
 
TPSSh 1.3937
49
1.3546
129
1.3550
129
1.3538
129
1.3285
553
1.3235
129
1.3265
563
1.3193
129
1.3356
49
1.3291
520
1.3929
16
  1.3206
125
1.2849
6
1.3224
129
1.3213
563
1.3443
22
1.3214
121
1.3151
115
1.3552
18
  1.1896
2
1.1736
3
1.2124
8
1.2143
7
 
wB97X-D 1.3660
63
1.3390
63
1.3447
606
1.3403
63
1.3220
605
1.3132
63
1.3231
605
1.3081
63
1.3187
606
1.3085
63
1.3820
16
  1.3190
605
1.2751
6
1.3229
605
1.3178
606
1.3223
25
1.3132
63
1.3187
599
1.3194
25
  1.1812
2
1.1705
2
1.2022
8
1.1956
8
 
B97D3 1.4107
26
1.3586
580
1.3830
26
1.3824
26
1.3354
578
1.3538
26
1.3370
580
1.3442
26
1.3327
580
1.3483
26
1.3255
630
  1.3502
26
1.2894
6
1.3511
26
1.3315
575
1.3594
19
1.3513
26
1.3332
572
1.3603
18
  1.1952
2
1.1834
2
1.2180
8
1.2109
8
 
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 daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Moller Plesset perturbation MP2 1.3766
319
1.3717
541
1.3738
506
1.3787
507
1.3351
598
1.3349
511
1.3365
535
1.3284
593
1.3275
501
1.3233
419
1.3573
19
1.2564
17
1.3355
571
1.3220
628
1.3318
511
1.3179
435
1.2872
63
1.3233
336
1.3218
292
1.2925
59
1.1810
3
1.2641
11
1.2416
8
1.2289
7
1.2083
8
1.2860
12
MP2=FULL 1.3736
315
1.3564
380
1.3579
349
1.3628
347
1.3376
525
1.3229
415
1.3271
423
1.3220
513
1.3148
323
1.3108
349
1.3548
19
1.1671
4
1.3135
200
1.2839
6
1.3163
379
1.3149
397
1.2837
63
1.3155
216
1.2970
231
1.2879
55
1.1778
3
1.2632
11
1.2396
8
1.2181
8
1.2034
8
1.2849
12
ROMP2 1.3921
35
1.3432
32
1.3335
34
1.3352
34
1.2916
34
1.2913
34
1.2944
33
1.2832
34
1.2836
34
1.2779
34
1.2421
3
  1.2728
22
1.2466
1
1.2836
34
1.2815
33
1.1386
1
1.2869
32
1.2189
7
1.2539
4
  1.1945
2
1.1829
2
1.1488
1
1.1392
1
 
MP3 1.2152
4
1.1837
4
1.1837
4
1.1900
4
1.3278
473
1.1682
4
1.3231
553
1.1573
4
1.1570
4
1.1580
4
1.3448
19
1.1545
4
1.3055
115
1.2751
6
1.3087
115
1.3035
115
1.1533
4
1.1682
4
1.1575
4
1.1538
4
  1.1793
2
1.1673
2
1.2058
8
1.1382
4
 
MP3=FULL   1.3532
59
1.3540
59
1.3574
59
1.3231
545
1.3195
59
1.3213
519
1.3105
59
1.3104
59
1.3074
59
1.3758
16
  1.3083
112
1.2731
6
1.3116
112
1.3042
111
  1.3307
53
1.3151
40
    1.1787
2
1.1657
2
1.2152
7
1.1341
4
 
MP4 1.3623
11
1.3600
236
1.2844
9
1.2809
9
1.3202
266
1.1915
5
1.1932
5
1.2365
8
1.3126
201
1.2920
11
1.3897
14
1.1754
4
1.3214
133
1.2508
1
1.3251
138
1.3063
162
1.1744
4
1.3360
114
1.3237
85
1.1751
4
  1.2029
2
1.1829
3
1.1768
3
1.1617
4
 
MP4=FULL 1.2582
4
1.3667
144
1.2157
4
1.2229
4
1.3249
136
1.1876
4
1.1893
4
1.1779
4
1.3153
133
1.1739
4
1.3884
13
1.1730
4
1.1785
4
1.2484
1
1.3224
141
1.3101
109
1.1718
4
1.3322
120
1.3133
85
1.1724
4
  1.2022
2
1.1811
3
1.1760
3
1.1566
4
 
B2PLYP 1.3784
139
1.3478
138
1.3468
139
1.3505
138
1.3458
462
1.3164
139
1.3148
146
1.3118
139
1.3112
142
1.3072
176
1.3658
18
1.1515
3
1.3145
138
1.2837
6
1.3145
139
1.3229
489
1.1511
3
1.3170
128
1.3069
157
1.1513
3
  1.1894
2
1.1730
3
1.2116
8
1.2041
8
 
B2PLYP=FULL 1.3832
134
1.3428
143
1.3522
134
1.3559
133
1.3140
143
1.3209
134
1.3162
143
1.3166
134
1.3170
134
1.3142
134
1.3903
16
  1.3186
134
1.2831
6
1.3192
134
1.3160
134
  1.3216
123
1.3138
116
    1.1892
2
1.1725
3
1.2113
8
1.2027
8
 
B2PLYP=FULLultrafine 1.3813
67
1.3618
67
1.3624
67
1.3643
67
1.3400
280
1.3297
67
1.3314
67
1.3239
67
1.3241
67
1.3226
67
1.3903
16
  1.3258
67
1.2831
6
1.3276
67
1.3231
67
  1.3318
67
1.3220
65
    1.1892
2
1.1725
3
1.2113
8
1.2027
8
 
Configuration interaction CID 1.2771
7
1.3412
313
1.3387
303
1.3415
302
1.3079
401
1.1680
5
1.1685
5
1.2979
307
1.2548
17
1.2672
11
1.3390
19
1.1507
4
1.1542
4
1.2689
6
1.2255
11
1.2177
11
1.1493
4
1.1643
4
1.1534
4
1.1497
4
  1.1782
2
1.1657
2
1.2107
7
1.1348
4
 
CISD 1.2749
8
1.3452
314
1.3410
306
1.3433
304
1.3097
402
1.2867
6
1.1768
6
1.2985
308
1.2558
17
1.2650
10
1.3408
19
1.1523
4
1.1563
4
1.2703
6
1.2274
11
1.2192
11
1.1509
4
1.1662
4
1.1550
4
1.1512
4
  1.1816
2
1.1683
2
1.2124
7
1.1366
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 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 daug-cc-pVDZ daug-cc-pVTZ Sadlej_pVTZ
Quadratic configuration interaction QCISD 1.4262
40
1.3741
452
1.3597
313
1.3645
321
1.3210
380
1.3244
328
1.3257
326
1.3130
351
1.3177
324
1.3123
288
1.3554
19
1.1622
4
1.3188
186
1.2827
6
1.3205
317
1.3056
263
1.1596
5
1.3226
183
1.3061
176
1.1600
5
1.1554
1
1.1914
2
1.1713
3
1.2250
7
1.1466
4
 
QCISD(T) 1.2344
4
1.2652
8
1.2688
8
1.2691
8
1.3169
255
1.1848
5
1.2860
13
1.3430
67
1.3084
18
1.2313
7
1.3858
14
1.1679
4
1.3214
143
1.2461
1
1.3119
196
1.3077
154
1.1667
4
1.3241
134
1.2983
98
1.1673
4
  1.1957
2
1.1772
3
1.1680
3
1.1526
4
 
QCISD(T)=FULL         1.3206
86
  1.3280
81
      1.4394
11
    1.2437
1
1.3205
81
1.3167
65
1.3212
25
1.3427
66
1.3141
42
1.2811
20
  1.1950
2
1.1755
3
1.1672
3
1.1480
4
 
QCISD(TQ) 1.2260
4
1.1973
4
1.1973
4
1.2041
4
1.2973
29
1.1785
4
1.2929
26
1.1684
4
1.1682
4
1.1681
4
1.3248
8
1.1653
4
1.1683
4
1.2439
1
1.2836
26
1.2670
19
1.1771
10
1.3223
23
1.1820
13
1.1427
2
      1.1444
1
1.1339
2
 
QCISD(TQ)=FULL         1.3345
27
  1.2855
17
      1.1866
3
    1.2418
1
1.2961
25
1.2256
15
1.1533
4
1.3515
19
1.1810
8
1.1449
3
      1.1436
1
1.1289
1
 
Coupled Cluster CCD 1.4239
40
1.3537
325
1.3510
305
1.3559
314
1.3341
426
1.3167
317
1.3190
315
1.3076
312
1.3104
262
1.3080
264
1.3473
19
1.1575
4
1.3147
178
1.2775
6
1.3151
309
1.2963
215
1.1545
5
1.3114
192
1.2894
141
1.1550
5
  1.3045
4
1.2665
5
1.2192
7
1.1416
4
 
CCSD 1.2233
4
1.2554
8
1.2589
8
1.2605
8
1.3160
298
1.2385
10
1.2854
18
1.3052
17
1.3707
26
1.3064
122
1.3521
19
1.1602
4
1.3094
153
1.2806
6
1.3109
195
1.3113
222
1.2540
39
1.3190
137
1.3106
145
1.1896
17
  1.1878
2
1.1686
3
1.2224
7
1.1443
4
 
CCSD=FULL 1.2232
4
1.1928
4
1.1928
4
1.2003
4
1.3128
190
1.1734
4
1.1743
4
1.1630
4
1.1627
4
1.3059
112
1.3493
19
1.1580
4
1.3090
151
1.2785
6
1.3076
151
1.3017
181
1.2587
41
1.3237
136
1.2972
134
1.1817
18
  1.1871
2
1.1731
2
1.2215
7
1.1399
4
 
CCSD(T) 1.2325
4
1.2667
12
1.2666
8
1.2672
8
1.3279
257
1.3349
74
1.3447
32
1.3180
66
1.3492
30
1.3399
22
1.3733
17
1.2335
7
1.3189
138
1.2454
1
1.3143
192
1.3001
170
1.2610
44
1.3220
158
1.2913
97
1.2389
30
1.1622
1
1.2604
7
1.1778
6
1.1669
3
1.1568
3
 
CCSD(T)=FULL 1.2325
4
1.2007
4
1.2007
4
1.2073
4
1.3215
185
1.1793
4
1.1805
4
1.1694
4
1.1692
4
1.1665
4
1.3817
14
1.1648
4
1.3182
151
1.2429
1
1.3154
167
1.3048
121
1.2914
43
1.3270
133
1.2924
82
1.2643
29
  1.2595
7
1.2393
8
1.1662
3
1.1470
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 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 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 1.1931
7
1.1769
8
  1.2535
12
1.3609
512
1.3190
497
1.3480
512
1.3165
500
1.3507
513
1.3521
511
ROHF 1.2124
5
1.2066
5
               
density functional LSDA 1.1589
4
1.1502
4
    1.2169
4
1.1939
4
1.2130
4
1.1858
4
1.1991
4
1.1990
4
BLYP 1.2234
8
1.2159
8
    1.2217
4
1.1968
4
1.2183
4
1.1889
4
1.2132
4
1.2135
4
B1B95 1.1816
6
1.2054
7
    1.3679
251
1.3383
248
1.2421
6
1.2155
6
1.2377
6
1.2378
6
B3LYP 1.2083
8
1.2011
8
  1.2772
12
1.3737
512
1.3441
496
1.3715
509
1.3412
498
1.3639
510
1.3637
509
B3LYPultrafine 1.2083
8
1.2011
8
    1.2081
4
1.1847
4
1.2049
4
1.1768
4
1.2083
5
1.1988
4
B3PW91 1.2059
8
1.1989
8
    1.2051
4
1.1825
4
1.2017
4
1.1748
4
1.1961
4
1.1962
4
mPW1PW91 1.2014
8
1.1960
8
    1.2020
4
1.1797
4
1.1987
4
1.1721
4
1.1932
4
1.1934
4
M06-2X 1.2005
8
1.1945
8
    1.1948
4
1.1748
4
1.1905
4
1.1652
4
1.1907
4
1.1908
4
PBEPBE 1.2192
8
1.2124
8
  1.2854
12
1.2178
4
1.1940
4
1.2142
4
1.1864
4
1.2097
4
1.2099
4
PBEPBEultrafine 1.2192
8
1.2124
8
    1.2178
4
1.1940
4
1.2142
4
1.1864
4
1.2097
4
1.2100
4
PBE1PBE 1.2018
8
1.1965
8
    1.2024
4
1.1801
4
1.1990
4
1.1726
4
1.1938
4
1.1940
4
HSEh1PBE 1.2030
8
1.1964
8
    1.2030
4
1.1806
4
1.1998
4
1.1731
4
1.1939
4
1.1941
4
TPSSh 1.2124
8
1.2143
7
               
wB97X-D 1.2022
8
1.1956
8
    1.3564
63
1.3267
63
1.3535
63
1.3223
63
1.3463
63
1.3463
63
B97D3 1.2180
8
1.2109
8
               
Moller Plesset perturbation MP2 1.2289
7
1.2083
8
  1.2860
12
1.3960
517
1.3494
497
1.3883
515
1.3464
499
1.3851
519
1.3847
517
MP2=FULL 1.2181
8
1.2034
8
  1.2849
12
1.2320
4
1.1971
4
1.2256
4
1.1895
4
1.2210
4
1.2209
4
ROMP2 1.1488
1
1.1392
1
               
MP3 1.2058
8
1.1382
4
    1.2110
4
1.1828
4
1.2033
4
1.1744
4
1.1983
4
1.1981
4
MP3=FULL 1.2152
7
1.1341
4
               
MP4 1.1768
3
1.1617
4
    1.2440
4
1.2019
4
1.2388
4
1.1956
4
1.2331
4
1.2333
4
MP4=FULL 1.1760
3
1.1566
4
    1.2440
4
1.2019
4
1.2388
4
1.1956
4
1.2330
4
1.2330
4
B2PLYP 1.2116
8
1.2041
8
    1.2032
3
1.1767
3
1.1995
3
1.1688
3
1.1934
3
1.1936
3
B2PLYP=FULL 1.2113
8
1.2027
8
               
B2PLYP=FULLultrafine 1.2113
8
1.2027
8
               
Configuration interaction CID 1.2107
7
1.1348
4
    1.2095
4
1.1791
4
1.2025
4
1.1706
4
1.1977
4
1.1975
4
CISD 1.2124
7
1.1366
4
    1.2130
4
1.1811
4
1.2058
4
1.1726
4
1.2009
4
1.2007
4
Quadratic configuration interaction QCISD 1.2250
7
1.1466
4
    1.2254
4
1.1912
4
1.2183
4
1.1833
4
1.2133
4
1.2131
4
QCISD(T) 1.1680
3
1.1526
4
    1.2292
4
1.1951
4
1.2226
4
1.1878
4
1.2171
4
1.2169
4
QCISD(T)=FULL 1.1672
3
1.1480
4
               
QCISD(TQ) 1.1444
1
1.1339
2
    1.2246
4
1.1928
4
1.2176
4
1.1851
4
1.2125
4
1.2123
4
QCISD(TQ)=FULL 1.1436
1
1.1289
1
               
Coupled Cluster CCD 1.2192
7
1.1416
4
    1.2170
4
1.1857
4
1.2100
4
1.1777
4
1.2051
4
1.2049
4
CCSD 1.2224
7
1.1443
4
    1.2213
4
1.1887
4
1.2142
4
1.1807
4
1.2093
4
1.2091
4
CCSD=FULL 1.2215
7
1.1399
4
    1.2213
4
1.1887
4
1.2142
4
1.1807
4
1.2091
4
1.2088
4
CCSD(T) 1.1669
3
1.1568
3
    1.2282
4
1.1943
4
1.2215
4
1.1868
4
1.2160
4
1.2159
4
CCSD(T)=FULL 1.1662
3
1.1470
4
    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.