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Comparison of levels of theory for Cl-Cl


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 1.9546
5
PM3 2.1485
6
PM6 2.0479
5
composite G2 2.2094
6
G3 2.2094
6
G3B3 2.2551
6
G3MP2 1.9316
2
G4 2.2162
6
CBS-Q 2.2094
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ cc-pCVQZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
hartree fock HF 2.2192
6
2.3551
6
2.2104
6
2.3373
6
2.2041
6
2.2041
6
2.2051
6
2.2138
6
2.2137
6
2.1789
6
1.9390
3
1.9742
1
2.2078
6
2.2093
6
2.1841
6
2.1180
4
2.2078
6
2.1825
6
2.1171
4
1.9904
1
2.1581
3
2.2477
2
1.9423
2
1.9171
2
1.9726
1
1.9761
1
2.0101
1
1.9487
2
2.2195
5
ROHF   2.3922
2
2.2660
2
2.3828
2
2.2726
2
2.2726
2
2.2754
2
2.2883
2
2.2883
2
  1.8580
1
  2.2778
2
2.2733
2
2.2562
2
2.2521
2
2.2780
2
2.2549
2
2.2504
2
  2.2494
2
2.2479
2
1.8820
1
1.8589
1
      1.8900
1
1.8690
1
density functional LSDA 2.2625
6
2.1913
3
2.2140
6
2.3509
6
2.2111
6
2.2111
6
2.2119
6
2.2271
6
2.2272
6
2.1718
6
1.9747
2
1.9767
1
2.2726
5
2.2095
6
2.1814
6
2.1585
3
2.2004
6
2.1777
6
2.1549
3
1.9928
1
2.2433
2
2.2346
2
1.9694
2
1.9354
2
1.9754
1
1.9801
1
  2.0151
1
1.9920
1
BLYP 2.3311
6
2.4478
6
2.3123
6
2.4447
6
2.1788
6
2.3111
6
2.3118
6
2.3276
6
2.3277
6
2.2721
6
2.0090
3
2.0411
1
2.3143
6
2.3086
6
2.2818
6
2.0488
1
2.0501
3
2.0253
3
2.0484
1
2.0265
1
2.3717
2
2.3619
2
2.0288
2
1.9933
2
2.0385
1
2.0434
1
  2.0307
2
2.0067
2
B1B95 2.2673
6
1.9595
2
2.2275
6
2.3625
6
2.2237
6
2.2237
6
2.2238
6
2.2373
6
2.2373
6
2.1889
6
1.9795
1
1.9795
1
2.2245
6
2.2243
6
2.1963
6
2.1750
3
2.2177
6
2.1926
6
2.1723
3
1.9940
1
2.1728
3
2.2614
2
1.9618
2
1.9320
2
1.9776
1
1.9817
1
  1.9663
2
1.9436
2
B3LYP 2.2910
6
2.4055
6
2.2642
6
2.3957
6
2.2615
6
2.2615
6
2.2625
6
2.2766
6
2.2766
6
2.2268
6
1.9776
3
2.0106
1
2.2657
6
2.2615
6
2.2351
6
2.1673
4
2.2547
6
2.2317
6
2.1651
4
2.0118
1
2.2126
3
2.3062
2
1.9940
2
1.9616
2
2.0085
1
2.0135
1
2.0501
1
1.9971
2
1.9738
2
B3LYPultrafine 2.1190
1
2.2298
3
2.0446
1
2.2036
1
2.2618
6
2.0137
3
2.0160
3
2.0244
3
2.0563
1
1.9848
3
1.9774
3
2.0099
1
2.2023
4
2.2622
6
2.2352
6
2.0167
1
2.2554
6
2.2225
6
2.0163
1
2.0112
1
2.3126
2
2.3060
2
1.9416
1
1.9104
1
  2.0135
1
  1.9964
2
1.9735
2
B3PW91 2.2769
6
2.3853
6
2.2385
6
2.3723
6
2.2342
6
2.2343
6
2.2346
6
2.2465
6
2.2464
6
2.1983
6
1.9569
3
1.9887
1
2.2363
6
2.2344
6
2.2057
6
1.9964
1
1.9955
3
1.9719
3
1.9961
1
1.9998
1
2.2798
2
2.2731
2
1.9732
2
1.9416
2
1.9875
1
1.9918
1
  1.9773
2
1.9542
2
mPW1PW91 2.2658
6
2.3745
6
2.2267
6
2.3602
6
2.2223
6
2.2224
6
2.2230
6
2.2342
6
2.2342
6
2.1873
6
1.9502
3
1.9824
1
2.2246
6
2.2228
6
2.1946
6
1.9889
1
2.2160
6
2.1916
6
1.9887
1
1.9957
1
2.2656
2
2.2592
2
1.9652
2
1.9351
2
1.9809
1
1.9850
1
  1.9698
2
1.9470
2
M06-2X 2.2468
6
2.3538
6
2.2135
6
2.3396
6
2.2097
6
2.2098
6
2.2107
6
2.2212
6
2.2212
6
2.1821
6
2.1770
6
1.9856
1
2.2138
6
2.2125
6
2.1880
6
1.9908
1
2.2080
6
2.1858
6
1.9906
1
1.9988
1
2.2519
2
2.2480
2
1.9623
2
1.9334
2
1.9826
1
1.9874
1
  1.9675
2
1.9444
2
PBEPBE 2.3023
6
2.4120
6
2.2662
6
2.4034
6
2.2631
6
2.2632
6
2.2643
6
2.2779
6
2.2779
6
2.2223
6
1.9749
3
2.0059
1
2.2643
6
2.2608
6
2.2305
6
2.2143
3
2.2517
6
2.2265
6
2.2102
3
2.0087
1
2.2102
3
2.3027
2
1.9945
2
1.9612
2
2.0037
1
2.0085
1
2.0225
1
1.9979
2
1.9745
2
PBEPBEultrafine 2.1251
1
2.2367
3
2.0443
1
2.2082
1
2.2635
6
2.0140
3
2.0166
3
2.0244
3
2.0558
1
1.9815
3
1.9747
3
2.0052
1
2.2008
4
2.2617
6
2.2306
6
2.0128
1
2.2526
6
2.2267
6
2.0125
1
2.0080
1
2.3116
2
2.3024
2
1.9461
1
1.9147
1
  2.0085
1
  1.9971
2
1.9742
2
PBE1PBE 2.2623
6
1.9586
2
2.2234
6
2.3576
6
2.2188
6
2.2188
6
2.2196
6
2.2308
6
2.2309
6
2.1834
6
1.9478
3
1.9799
1
2.2208
6
2.2192
6
2.1906
6
1.9873
1
2.2124
6
2.1876
6
1.9871
1
1.9941
1
2.2611
2
2.2547
2
1.9627
2
1.9329
2
1.9782
1
1.9825
1
  1.9674
2
1.9448
2
HSEh1PBE 2.2655
6
2.3769
6
2.2280
6
2.3630
6
2.2238
6
2.2238
6
2.2245
6
2.2364
6
2.2365
6
2.1883
6
1.9498
3
1.9820
1
2.2262
6
2.2239
6
2.1958
6
1.9886
1
2.2169
6
2.1927
6
1.9880
1
1.9955
1
2.2669
2
2.2605
2
1.9651
2
1.9347
2
1.9802
1
1.9846
1
  1.9695
2
1.9468
2
TPSSh 2.1317
2
2.3543
4
2.1840
4
2.3375
4
2.1507
6
2.1839
4
2.1517
6
2.1945
4
1.9955
2
2.1300
6
1.9502
2
  2.1869
4
2.1854
4
2.1339
6
1.9580
2
2.1804
4
2.1547
4
1.9580
2
  2.2931
2
2.2870
2
1.9827
2
1.9504
2
1.9955
1
1.9999
1
  1.9873
2
1.9629
2
wB97X-D 2.1110
2
2.1906
2
2.1400
6
2.1493
2
2.1357
6
1.9678
2
2.1365
6
1.9746
2
2.1420
6
1.9442
2
1.9378
2
  2.1387
6
2.1370
6
2.1217
6
1.9448
2
1.9752
2
2.1215
6
1.9449
2
  1.8870
1
1.8887
1
1.9666
2
1.9386
2
1.9853
1
    1.9713
2
1.9496
2
B97D3 2.1589
2
2.4208
6
2.0105
2
2.2097
2
2.2862
6
2.0105
2
2.2869
6
2.0187
2
2.2973
6
1.9735
2
2.2466
6
  2.2902
6
2.0111
2
2.2601
6
1.9731
2
2.0086
2
2.2536
6
1.9730
2
  1.9141
1
1.9156
1
2.0016
2
1.9654
2
2.0106
1
    2.0045
2
2.2534
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ cc-pCVQZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Moller Plesset perturbation MP2 2.2572
6
2.4212
6
2.2277
6
2.4097
6
2.1422
6
2.2234
6
2.2260
6
2.1468
6
2.2328
6
2.1764
6
1.9542
3
1.9845
1
2.2205
6
2.2256
6
2.1806
6
2.1073
4
2.2302
6
2.1801
6
2.1060
4
2.0026
1
2.1526
3
2.2313
2
1.9798
2
1.9419
2
1.9777
1
1.9888
1
2.0228
1
1.9951
2
1.9542
2
MP2=FULL 2.2571
6
2.4215
6
2.2274
6
2.4100
6
2.2230
6
2.2231
6
2.2256
6
2.2320
6
2.2321
6
2.1717
6
1.9495
3
1.9797
1
2.2198
6
2.2251
6
2.1755
6
2.1035
4
2.2292
6
2.1724
6
2.1010
4
2.0016
1
2.1462
3
2.2218
2
1.9783
2
1.9382
2
1.9729
1
1.9848
1
2.0223
1
1.9950
2
1.9475
2
ROMP2 2.5363
1
  2.6508
1
2.7576
1
2.6624
1
2.6624
1
2.6652
1
2.6813
1
2.6813
1
2.5835
1
    2.6427
1
2.6399
1
2.5859
1
  2.6444
1
      2.5801
1
2.5711
1
             
MP3 2.1126
1
2.2691
1
2.0289
1
2.2428
1
2.2314
6
2.0255
1
2.1477
6
2.0372
1
2.0372
1
2.0066
1
1.9644
3
1.9968
1
2.1677
4
2.1710
4
2.1336
4
1.9960
1
2.0513
1
2.0105
1
1.9961
1
2.0091
1
2.2488
2
2.2479
2
1.9859
2
1.9488
2
1.9892
1
2.0008
1
  2.0012
2
1.9608
2
MP3=FULL   2.2655
2
1.9862
2
2.2284
2
2.1470
6
1.9848
2
2.1483
6
1.9906
2
1.9909
2
1.9549
2
1.9442
2
  2.1675
4
2.1704
4
2.1298
4
  2.0060
2
1.9576
2
    2.2441
2
2.2399
2
1.9845
2
1.9460
2
1.9849
1
1.9977
1
  2.0011
2
1.9542
2
MP4 2.1231
1
2.4710
5
2.0410
1
2.2581
1
2.3064
5
2.0353
1
2.0392
1
2.0490
1
2.3186
5
2.0116
1
2.0048
2
2.0039
1
2.3012
5
2.3048
5
2.2584
5
2.0016
1
2.3118
5
2.2593
5
2.0019
1
2.0316
1
2.5962
1
2.5905
1
      2.0080
1
  2.0603
1
2.0173
1
MP4=FULL 2.1229
1
2.4710
5
2.0414
1
2.2588
1
2.3062
5
2.0351
1
2.0393
1
2.0488
1
2.3179
5
2.0063
1
1.9997
2
1.9989
1
2.0464
1
2.3043
5
2.2531
5
1.9985
1
2.3106
5
2.2509
5
1.9982
1
  2.5898
1
2.5802
1
      2.0040
1
  2.0603
1
2.0095
1
B2PLYP 2.2374
4
2.3685
4
2.1761
4
2.3501
4
2.1769
4
2.1770
4
2.1793
4
2.1909
4
2.1910
4
2.1446
4
1.9689
3
2.0000
1
2.1824
4
2.1799
4
2.0217
4
2.0046
1
2.1804
4
2.1488
4
2.0044
1
2.0072
1
2.2760
2
2.2716
2
1.9871
2
1.9534
2
1.9963
1
2.0031
1
  1.9951
2
1.9659
2
B2PLYP=FULL 2.2374
4
2.3686
4
2.1760
4
2.3502
4
2.1768
4
2.1769
4
2.1792
4
2.1907
4
2.1908
4
2.1431
4
1.9520
2
  2.1822
4
2.1797
4
2.1484
4
  2.1801
4
2.1465
4
    2.2742
2
2.2687
2
1.9867
2
1.9524
2
1.9950
1
2.0020
1
  1.9951
2
1.9638
2
B2PLYP=FULLultrafine 2.1293
2
2.2512
2
1.9914
2
2.2109
2
2.3627
7
1.9901
2
1.9924
2
1.9989
2
1.9990
2
1.9602
2
1.9518
2
  1.9982
2
2.3647
7
2.3332
7
  1.9995
2
2.3312
7
    1.9025
1
1.9038
1
1.9379
1
1.9040
1
      1.9944
2
1.9636
2
Configuration interaction CID 2.1288
1
2.4046
6
2.2218
6
2.3939
6
2.2175
6
2.0144
1
2.0171
1
2.2245
6
2.0252
1
1.9932
1
1.9497
3
1.9831
1
2.0261
1
1.9997
3
1.9624
3
1.9818
1
2.0346
1
1.9952
1
1.9816
1
  2.2386
2
2.2354
2
1.9710
2
1.9327
2
1.9748
1
1.9859
1
  1.9818
2
1.9431
2
CISD 2.1300
1
2.4120
6
2.2246
6
2.4023
6
2.2201
6
  2.0192
1
2.2273
6
2.0273
1
1.9943
1
1.9512
3
1.9843
1
2.0279
1
2.0020
3
1.9638
3
1.9827
1
2.0364
1
1.9963
1
1.9825
1
  2.2402
2
2.2367
2
1.9731
2
1.9340
2
1.9757
1
1.9870
1
  1.9838
2
1.9444
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ cc-pCVQZ aug-cc-pCVTZ Sadlej_pVTZ daug-cc-pVDZ daug-cc-pVTZ
Quadratic configuration interaction QCISD 2.1300
1
2.4279
6
2.2405
6
2.4192
6
2.2360
6
2.2361
6
2.2395
6
2.2447
6
2.2447
6
2.1913
6
1.9648
3
1.9974
1
2.2334
6
2.2384
6
2.1955
6
1.9953
1
2.2435
6
2.1948
6
1.9953
1
2.0106
1
2.1663
3
2.2473
2
1.9862
2
1.9475
2
1.9884
1
2.0006
1
  1.9996
2
1.9590
2
QCISD(T) 2.1305
1
2.2956
1
2.0453
1
2.2683
1
2.3092
5
2.0386
1
2.0428
1
2.0589
2
2.0529
1
2.0139
1
2.0081
2
2.0060
1
2.3034
5
2.3078
5
2.2605
5
2.0032
1
2.3145
5
2.2612
5
2.0035
1
  2.5989
1
2.5961
1
      2.0097
1
  2.0634
1
2.0191
1
QCISD(T)=FULL         2.0482
2
  2.0525
2
      2.0041
1
    2.0627
2
2.0159
2
2.0024
2
2.0698
2
2.0154
2
2.0018
2
                2.0634
1
2.0112
1
QCISD(TQ)   2.2989
1
2.0467
1
2.2722
1
2.0403
1
2.0402
1
2.0445
1
2.0542
1
2.0542
1
2.0160
1
2.0079
1
2.0079
1
2.0520
1
2.0567
1
2.0199
1
2.0050
1
2.0651
1
2.0217
1
2.0052
1
                   
QCISD(TQ)=FULL         2.0400
1
  2.0444
1
            2.0563
1
2.0151
1
2.0017
1
2.0652
1
2.0142
1
                     
Coupled Cluster CCD 2.1288
1
2.4148
6
2.2326
6
2.4044
6
2.2284
6
2.2285
6
2.2311
6
2.2365
6
2.2366
6
2.1867
6
1.9615
3
1.9948
1
2.2266
6
2.2321
6
2.1905
6
1.9931
1
2.2372
6
2.1898
6
1.9932
1
2.0091
1
2.1632
3
2.2439
2
1.9824
2
1.9446
2
1.9859
1
1.9983
1
  1.9955
2
1.9558
2
CCSD 2.1300
1
2.2871
1
2.0334
1
2.2608
1
2.2346
6
1.9764
2
1.9793
2
1.9859
2
1.9859
2
1.9746
3
1.9643
3
1.9971
1
2.2321
6
2.2374
6
2.1946
6
2.1205
4
2.2424
6
2.1939
6
2.1196
4
  2.2488
2
2.2468
2
1.9856
2
1.9469
2
1.9882
1
2.0003
1
  1.9990
2
1.9585
2
CCSD=FULL 2.1298
1
2.2872
1
2.0334
1
2.2611
1
2.2341
6
2.0280
1
2.0317
1
2.0390
1
2.0390
1
1.9695
3
1.9592
3
1.9919
1
2.2311
6
2.2367
6
2.1894
6
2.1166
4
2.2414
6
2.1859
6
2.1144
4
  2.2431
2
2.2377
2
1.9828
2
1.9426
2
1.9824
1
1.9957
1
  1.9987
2
1.9512
2
CCSD(T) 2.1305
1
2.2959
1
2.0449
1
2.2686
1
2.3089
5
2.0481
2
2.0522
2
2.0586
2
2.0586
2
2.0164
2
2.0079
2
2.0058
1
2.3031
5
2.3077
5
2.2605
5
2.2001
3
2.3141
5
2.2609
5
2.1990
3
2.0351
1
2.3034
2
2.5960
1
      2.0093
1
  2.0633
1
2.0189
1
CCSD(T)=FULL 2.1303
1
2.2964
1
2.0452
1
2.2693
1
2.3086
5
2.0382
1
2.0426
1
2.0516
1
2.0515
1
2.0084
1
2.0024
2
2.0008
1
2.3022
5
2.3071
5
2.2549
5
2.1965
3
2.3130
5
2.2524
5
2.1939
3
2.0338
1
2.2976
2
2.5861
1
      2.0062
1
  2.0632
1
2.0110
1
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(D+d)Z cc-pV(T+d)Z aug-cc-pV(T+d)Z cc-pCVDZ cc-pCVTZ cc-pCVQZ 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 2.3281
6
2.1997
6
2.3293
6
2.2000
6
2.3406
6
2.3489
6
    2.1080
6
ROHF                 1.8587
1
density functional LSDA 2.1913
1
2.0353
1
2.1923
1
2.0338
1
2.2117
1
2.2045
1
    1.9729
1
BLYP 2.2355
1
2.0838
1
2.2353
1
2.0817
1
2.2543
1
2.2588
1
    1.9941
2
B1B95 2.1847
1
2.0301
1
2.1812
1
2.0255
1
2.2049
1
2.2025
1
    1.9318
2
B3LYP 2.3958
6
2.2590
6
2.3955
6
2.2580
6
2.4056
6
2.4069
6
    2.1362
6
B3LYPultrafine 2.2019
1
2.0502
1
2.2026
1
2.0485
1
2.2252
1
2.2303
1
    1.9624
2
B3PW91 2.1844
1
2.0312
1
2.1853
1
2.0299
1
2.2095
1
2.2133
1
    1.9416
2
mPW1PW91 2.1756
1
2.0232
1
2.1767
1
2.0220
1
2.2012
1
2.2055
1
    1.9347
2
M06-2X 2.1685
1
2.0196
1
2.1709
1
2.0183
1
2.1884
1
2.1931
1
    1.9355
2
PBEPBE 2.2077
1
2.0507
1
2.2079
1
2.0491
1
2.2298
1
2.2330
1
    2.1335
6
PBEPBEultrafine 2.2079
1
2.0496
1
2.2081
1
2.0479
1
2.2310
1
2.2345
1
    1.9599
2
PBE1PBE 2.1737
1
2.0205
1
2.1749
1
2.0193
1
2.1991
1
2.2037
1
    1.9322
2
HSEh1PBE 2.1775
1
2.0229
1
2.1785
1
2.0217
1
2.2025
1
2.2071
1
    1.9342
2
TPSSh                 1.9506
2
wB97X-D 2.1465
2
1.9764
2
2.1504
2
1.9774
2
2.1885
2
2.1899
2
    1.9384
2
B97D3                 1.9647
2
Moller Plesset perturbation MP2 2.4019
6
2.2135
6
2.4028
6
2.2145
6
2.4074
6
2.4129
6
    2.1144
6
MP2=FULL 2.2151
1
2.0233
1
2.2192
1
2.0235
1
2.2344
1
2.2474
1
    1.9381
2
MP3 2.2348
1
2.0361
1
2.2342
1
2.0352
1
2.2553
1
2.2591
1
    1.9502
2
MP3=FULL                 1.9482
2
MP4 2.2491
1
2.0431
1
2.2484
1
2.0426
1
2.2708
1
2.2748
1
    2.0075
1
MP4=FULL 2.2491
1
2.0431
1
2.2484
1
2.0426
1
2.2708
1
2.2765
1
    2.0049
1
B2PLYP 2.2038
1
2.0374
1
2.2063
1
2.0367
1
2.2262
1
2.2342
1
    1.9545
2
B2PLYP=FULL                 1.9537
2
B2PLYP=FULLultrafine                 1.9535
2
Configuration interaction CID 2.2356
1
2.0249
1
2.2300
1
2.0231
1
2.2585
1
2.2551
1
    1.9347
2
CISD 2.2412
1
2.0260
1
2.2358
1
2.0244
1
2.2645
1
2.2605
1
    1.9361
2
Quadratic configuration interaction QCISD 2.2527
1
2.0377
1
2.2514
1
2.0370
1
2.2766
1
2.2773
1
    1.9504
2
QCISD(T) 2.2581
1
2.0461
1
2.2582
1
2.0458
1
2.2833
1
2.2858
1
    2.0114
1
QCISD(T)=FULL                 2.0086
1
QCISD(TQ) 2.2612
1
2.0478
1
2.2617
1
2.0475
1
2.2858
1
2.2881
1
     
Coupled Cluster CCD 2.2454
1
2.0356
1
2.2429
1
2.0344
1
2.2689
1
2.2694
1
    1.9468
2
CCSD 2.2526
1
2.0375
1
2.2511
1
2.0367
1
2.2763
1
2.2767
1
    1.9499
2
CCSD=FULL 2.2526
1
2.0375
1
2.2511
1
2.0367
1
2.2763
1
2.2761
1
    1.9461
2
CCSD(T) 2.2584
1
2.0460
1
2.2585
1
2.0456
1
2.2834
1
2.2858
1
    2.0113
1
CCSD(T)=FULL 2.2584
1
2.0460
1
2.2585
1
2.0456
1
2.2834
1
2.2875
1
    2.0085
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.