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III.G.1.a.

Comparison of levels of theory for N-Br


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
composite G2 2.1034
1
G3 2.1102
1
G3B3 2.1768
1
G4 2.1615
1
CBS-Q 2.0874
1

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) TZVP cc-pVDZ cc-pVTZ cc-pVQZ aug-cc-pVDZ aug-cc-pVTZ aug-cc-pVQZ
hartree fock HF 1.9460
1
2.0641
1
2.0132
1
2.1207
1
2.1034
1
2.1034
1
2.0923
1
2.1593
1
2.1593
1
2.0470
1
2.1363
1
2.1534
1
2.1260
1
2.1263
1
2.1247
1
2.1204
1
2.1225
1
ROHF   2.0641
1
2.0132
1
2.1207
1
2.1034
1
2.1034
1
2.0923
1
2.1593
1
2.1593
1
    2.1534
1
2.1260
1
2.1263
1
2.1247
1
2.1204
1
2.1225
1
density functional LSDA 2.0463
1
2.0783
1
2.0783
1
2.1623
1
2.1017
1
2.1017
1
2.0850
1
2.1410
1
2.1410
1
2.0486
1
  2.1281
1
2.1066
1
  2.1019
1
2.0973
1
 
BLYP 2.1004
1
2.2004
1
2.1592
1
2.2456
1
2.1943
1
2.1943
1
2.1828
1
2.2424
1
2.2424
1
2.1597
1
  2.2254
1
2.2142
1
       
B1B95 2.0201
1
2.0759
1
2.0759
1
2.1678
1
2.1195
1
2.1195
1
2.1054
1
2.1591
1
2.1591
1
2.0709
1
  2.1520
1
2.1309
1
  2.1274
1
2.1232
1
 
B3LYP 2.0425
1
2.1504
1
2.1099
1
2.1960
1
2.1489
1
2.1489
1
2.1370
1
2.1928
1
2.1928
1
2.1072
1
2.1772
1
2.1780
1
2.1662
1
2.1602
1
2.1596
1
2.1566
1
2.1561
1
B3LYPultrafine         2.1471
1
                    2.1580
1
 
B3PW91 2.0349
1
2.1329
1
2.0899
1
2.1801
1
2.1302
1
2.1302
1
2.1158
1
2.1686
1
2.1686
1
2.0835
1
  2.1600
1
2.1403
1
       
mPW1PW91 2.0213
1
2.1208
1
2.0767
1
2.1687
1
2.1191
1
2.1191
1
2.1051
1
2.1570
1
2.1570
1
2.0717
1
  2.1500
1
2.1291
1
  2.1255
1
2.1216
1
 
PBEPBE 2.0797
1
2.1688
1
2.1275
1
2.2162
1
2.1619
1
2.1619
1
2.1470
1
2.2014
1
2.2014
1
2.1168
1
  2.1897
1
2.1703
1
  2.1673
1
2.1617
1
 
PBE1PBE         2.1167
1
                       
TPSSh         2.1679
1
  2.1587
1
          2.1651
1
       
Moller Plesset perturbation MP2 2.0474
1
2.2525
1
2.2055
1
2.3235
1
2.2100
1
2.2100
1
2.2037
1
2.2361
1
2.2361
1
2.1420
1
2.2195
1
2.2334
1
2.1818
1
  2.2121
1
2.1730
1
 
MP2=FULL 2.0473
1
2.2522
1
2.2044
1
2.3195
1
2.2042
1
2.2042
1
2.1967
1
2.2328
1
2.2328
1
2.1173
1
  2.2317
1
2.1735
1
  2.2091
1
2.1565
1
 
MP3         2.1560
1
  2.1698
1
                   
MP3=FULL         2.1654
1
  2.1564
1
                   
MP4   2.3379
1
    2.2303
1
      2.2571
1
      2.1990
1
       
B2PLYP                         2.1689
1
       
Configuration interaction CID   2.1408
1
2.0933
1
2.1929
1
2.1264
1
    2.1488
1
                 
CISD   2.1407
1
2.0921
1
2.1934
1
2.1271
1
    2.1494
1
                 
Quadratic configuration interaction QCISD   2.1730
1
2.1173
1
2.2249
1
2.1472
1
2.1472
1
2.1336
1
2.1681
1
2.1681
1
2.0744
1
  2.1698
1
2.1154
1
  2.1381
1
2.1023
1
 
QCISD(T)         2.1807
1
            2.2048
1
2.1473
1
       
Coupled Cluster CCD   2.1830
1
2.1330
1
2.2313
1
2.1508
1
2.1508
1
2.1380
1
2.1656
1
2.1656
1
2.0769
1
  2.1717
1
2.1165
1
  2.1432
1
2.1055
1
 
CCSD         2.1439
1
            2.1674
1
2.1119
1
       
CCSD(T)         2.1774
1
            2.2028
1
2.1446
1
2.1329
1
2.1672
1
2.1341
1
2.1224
1
CCSD(T)=FULL         2.1709
1
            2.2011
1
2.1392
1
  2.1643
1
2.1179
1
 

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 2.0690
1
  2.0773
1
  2.1220
1
2.0879
1
density functional B3LYP 2.1686
1
  2.1735
1
  2.1999
1
2.1799
1
Moller Plesset perturbation MP2 2.3213
1
  2.3164
1
  2.3288
1
2.3200
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.