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Bad Calculated Bond Lengths

List of molecules with calculated bond lengths that differ by more than 0.050 Å from experimental bond lengths.

Calculated at BLYP/3-21G

17 02 03 13 22
Species Name Bond type Bond Length (Å)
Experimental Calculated Difference
CCl4 Carbon tetrachloride rCCl 1.767 1.878 0.111
CHCl3 Chloroform rCCl 1.762 1.879 0.117
CH3SOCH3 Dimethyl sulfoxide rCS 1.799 1.992 0.193
CH3SOCH3 Dimethyl sulfoxide rSO 1.485 1.648 0.163
C2H6O2S Dimethyl sulfone rSO 1.431 1.610 0.179
C2H6O2S Dimethyl sulfone rCS 1.777 1.954 0.177
CH3CCl3 Ethane, 1,1,1-trichloro- rCCl 1.767 1.895 0.128
CH3Cl Methyl chloride rCCl 1.785 1.924 0.139
CH3I methyl iodide rCI 2.136 2.241 0.105
CH3SH Methanethiol rCS 1.818 1.934 0.116
CH2BrCl Methane, bromochloro- rCCl 1.755 1.914 0.159
CH3CH2Cl Ethyl chloride rCCl 1.789 1.944 0.155
C2H3Cl Ethene, chloro- rCCl 1.726 1.863 0.137
C2H5I Ethyl iodide rCI 2.151 2.261 0.110
CH3CH2SH ethanethiol rCS 1.820 1.947 0.127
CH2Cl2 Methylene chloride rCCl 1.767 1.894 0.127
CH3SCH3 Dimethyl sulfide rCS 1.802 1.923 0.121
CH3CHClCH3 Propane, 2-chloro- rCCl 1.798 1.960 0.162
CH3CHSHCH3 2-Propanethiol rCS 1.849 1.950 0.101
CH3CHCl2 Ethane, 1,1-dichloro- rCCl 1.766 1.911 0.145
CH2CCl2 Ethene, 1,1-dichloro- rCCl 1.710 1.836 0.126
CH3COCl Acetyl Chloride rCCl 1.798 2.016 0.218
CCl2O Phosgene rCCl 1.737 1.895 0.159
CHF2Cl difluorochloromethane rCCl 1.747 1.970 0.223
CBrCl3 Methane, bromotrichloro- rCCl 1.765 1.894 0.129
CF3Br Bromotrifluoromethane rCBr 1.923 2.033 0.109
CFCl3 Trichloromonofluoromethane rCCl 1.764 1.898 0.135
CF2Cl2 difluorodichloromethane rCCl 1.744 1.919 0.175
CF3Cl Methane, chlorotrifluoro- rCCl 1.752 1.939 0.187
SiCl3CH3 methyltrichlorosilane rSiCl 2.026 2.181 0.155
CH3CHClCH2CH3 Butane, 2-chloro- rCCl 1.781 1.964 0.183
CH2ClCHClCH3 Propane, 1,2-dichloro- rCCl 1.793 1.946 0.153
CH2ClCHCl2 1,1,2-trichloroethane rCCl 1.776 1.923 0.147
CHClCCl2 Trichloroethylene rCCl 1.714 1.830 0.116
CHClCCl2 Trichloroethylene rCCl 1.720 1.835 0.115
CHClCCl2 Trichloroethylene rCCl 1.712 1.813 0.101
CF2CCl2 difluorodichloroethylene rCCl 1.706 1.810 0.104
ClCOClCO Oxalyl chloride rCCl 1.744 1.923 0.179
C3H5Cl3 Propane, 1,2,3-trichloro- rCCl 1.790 1.969 0.179
C6H4Cl2 1,4-dichlorobenzene rCCl 1.729 1.852 0.123
C3H5ClO Oxirane, (chloromethyl)- rCCl 1.798 1.949 0.151
C3H7SH 1-Propanethiol rCS 1.820 1.946 0.126
CH2ClCH2Cl Ethane, 1,2-dichloro- rCCl 1.790 1.941 0.151
CH2ClCHO chloroacetaldehyde rCCl 1.782 1.929 0.147
CH3CHNOH Acetaldoxime rNO 1.408 1.511 0.103
C6H5Cl chlorobenzene rCCl 1.725 1.859 0.134
CH2ClCH2CH2CH3 Butane, 1-chloro- rCCl 1.780 1.943 0.163
C4H4S Thiophene rCS 1.714 1.828 0.114
CH2CClCHCH2 1,3-Butadiene, 2-chloro- rCCl 1.742 1.883 0.141
CHClCHCl Ethene, 1,2-dichloro-, (Z)- rCCl 1.717 1.833 0.116
CHClCHCl Ethene, 1,2-dichloro-, (E)- rCCl 1.718 1.852 0.134
C3H6S Thietane rCS 1.847 1.973 0.126
C3H3NO Isoxazole rCH 1.075 1.439 0.364
C2H2N2O Furazan rNO 1.373 1.492 0.119
C2H4O3 trioxolane124 rCN 1.303 2.288 0.985
C3H6S3 1,3,5-Trithiane rCS 1.801 1.917 0.116
CBrClF2 Methane, bromochlorodifluoro- rCCl 1.736 1.947 0.211
CH2BrF Methane, bromofluoro- rCBr 1.915 2.054 0.139
CH2FI fluoroiodomethane rCI 2.140 2.288 0.149
CF3OF Trifluoromethylhypofluorite rOF 1.421 1.521 0.100
C2H4S Thiirane rCS 1.815 1.970 0.155
CH3CCl(CH3)CH3 Propane, 2-chloro-2-methyl- rCCl 1.803 1.974 0.171
CI4 tetraiodomethane rCI 2.157 2.275 0.118
CH2ClCH2CH3 Propane, 1-chloro- rCCl 1.796 1.947 0.151
CH2ClCH2CH3 Propane, 1-chloro- rCCl 1.796 1.942 0.146
CH2SHCH2SH 1,2-Ethanedithiol rCS 1.819 1.949 0.130
CH3CH(CH3)ONO Isopropyl nitrite rON 1.414 1.584 0.170
C6H4Cl2 1,3-dichlorobenzene rCCl 1.736 1.851 0.116
C4H10O Methyl propyl ether rCC 1.530 1.104 -0.426
C4H10O Methyl propyl ether rCH 1.099 1.471 0.372
CH2CHCHClCH3 1-Butene, 3-chloro- rCCl 1.813 1.981 0.168
CH2ClCHCHCH3 2-Butene, 1-chloro- rCCl 1.807 1.936 0.129
CH2FCl fluorochloromethane rCCl 1.762 1.961 0.199
CH2ClI chloroiodomethane rCCl 1.774 1.914 0.140
CH3OCl methyl hypochlorite rOCl 1.674 1.883 0.209
CHFClBr fluorochlorobromomethane rCCl 1.745 1.941 0.196
CH3CCl2CH3 Propane, 2,2-dichloro- rCCl 1.799 1.926 0.127
CH3NO3 Methyl nitrate rNO 1.402 1.558 0.156
C5H6S Thiophene, 3-methyl- rCS 1.714 1.828 0.114
CH3SCH2CH3 Ethane, (methylthio)- rCS 1.804 1.934 0.130
CH3SCH2CH3 Ethane, (methylthio)- rCS 1.804 1.925 0.121
CH3ONO Methyl nitrite rNO 1.398 1.550 0.152
CH3SSCH3 Disulfide, dimethyl rSS 2.038 2.303 0.265
CH3SSCH3 Disulfide, dimethyl rCS 1.810 1.931 0.121
C2H5NO3 Nitric acid, ethyl ester rNO 1.407 1.555 0.148
CH2CHCH2CH2Cl 1-Butene, 4-chloro- rCCl 1.794 1.945 0.151
CH2ClCCCl 1,3-dichloropropyne rCCl 1.779 1.966 0.187
GaAs Gallium arsenide rGaAs 2.530 2.650 0.120
CaO Calcium monoxide rOCa 1.822 2.136 0.314
CCl2 dichloromethylene rCCl 1.711 1.915 0.204
C5H10S 2H-Thiopyran, tetrahydro- rCS 1.811 1.932 0.121
CFCl chlorofluoromethylene rCCl 1.714 1.998 0.284
C4H6S Thiophene, 2,5-dihydro- rCS 1.816 1.945 0.129
HCCl Chloromethylene rCCl 1.696 1.902 0.206
C2H2ClF 1-chloro-1-fluoroethylene rCCl 1.704 1.864 0.160
SF6 Sulfur Hexafluoride rSF 1.561 1.704 0.144
ClNO Nitrosyl chloride rNCl 1.975 2.124 0.149
SO2F2 Sulfuryl fluoride rFS 1.530 1.725 0.195
SO2F2 Sulfuryl fluoride rOS 1.405 1.573 0.168
C4H6 1-Methylcyclopropene rCH 1.085 4.238 3.153
C4H6 1-Methylcyclopropene rCH 1.087 3.470 2.383
C4H6 1-Methylcyclopropene rCC 1.476 2.292 0.816
C4H6 1-Methylcyclopropene rCH 1.087 1.849 0.762
C4H6 1-Methylcyclopropene rCH 1.098 1.795 0.697
C4H6 1-Methylcyclopropene rCH 1.098 1.778 0.680
C4H6 1-Methylcyclopropene rCH 1.070 1.549 0.479
C4H6 1-Methylcyclopropene rCC 1.515 1.097 -0.418
C4H6 1-Methylcyclopropene rCC 1.300 1.547 0.247
CH3SO2NH2 methanesulfonamide rCN 1.207 1.900 0.693
OH- hydroxide anion rOH 0.964 1.084 0.120
NHCl2 dichloroamine rNCl 1.760 1.948 0.188
CCl carbon monochloride rCCl 1.649 1.858 0.208
CBr Carbon monobromide rCBr 1.821 1.969 0.148
SiH2Cl2 dichlorosilane rSiCl 2.033 2.191 0.158
C2H6N2O2 Dimethylnitroamine rNN 1.382 1.482 0.100
C4H5NO Isoxazole, 5-methyl- rNO 1.403 1.525 0.122
CH3SSH Hydrogen methyl disulfide rSS 2.038 2.314 0.276
CH3SSH Hydrogen methyl disulfide rCS 1.823 1.930 0.107
CH2Cl chloromethyl radical rCCl 1.691 1.823 0.132
CH3S thiomethoxy rCS 1.791 1.905 0.114
SO2 Sulfur dioxide rSO 1.432 1.614 0.182
SO3 Sulfur trioxide rSO 1.418 1.605 0.187
AlCl3 Aluminum trichloride rAlCl 2.060 2.179 0.119
KCl Potassium Chloride rKCl 2.667 2.813 0.147
I2 Iodine diatomic rII 2.665 2.938 0.273
C2Cl2 dichloroacetylene rCCl 1.612 1.724 0.112
HClO4 perchloric acid rOCl 1.641 2.010 0.369
HClO4 perchloric acid rOCl 1.404 1.686 0.282
HClO4 perchloric acid rOCl 1.414 1.680 0.266
ClFO3 Perchloryl fluoride rFCl 1.598 1.917 0.319
ClFO3 Perchloryl fluoride rClO 1.400 1.674 0.274
PF5 Phosphorus pentafluoride rPF 1.534 1.639 0.105
H2SO4 Sulfuric acid rSO 1.574 1.785 0.211
H2SO4 Sulfuric acid rSO 1.422 1.590 0.168
HNO3 Nitric acid rNO 1.406 1.541 0.135
SOCl2 thionyl chloride rSCl 2.076 2.429 0.353
SOCl2 thionyl chloride rSO 1.443 1.597 0.154
PCl3 Phosphorus trichloride rPCl 2.043 2.288 0.245
Br2 Bromine diatomic rBrBr 2.281 2.503 0.222
KBr Potassium Bromide rKBr 2.821 2.988 0.167
F2+ flourine diatomic cation rFF 1.322 1.431 0.109
O2 Oxygen diatomic rOO 1.208 1.330 0.122
O2+ diatomic oxygen cation rOO 1.116 1.234 0.117
O2- oxygen diatomic anion rOO 1.350 1.457 0.107
Cl2+ chlorine diatomic cation rClCl 1.892 2.204 0.312
Cl2 Chlorine diatomic rClCl 1.988 2.261 0.273
HNO2 Nitrous acid rNO 1.442 1.574 0.132
F2SO Thionyl Fluoride rFS 1.585 1.762 0.177
F2SO Thionyl Fluoride rOS 1.413 1.577 0.165
NF3 Nitrogen trifluoride rNF 1.365 1.489 0.125
PF3 Phosphorus trifluoride rFP 1.561 1.673 0.112
SF4 Sulfur tetrafluoride rSF 1.545 1.719 0.174
SF4 Sulfur tetrafluoride rSF 1.646 1.777 0.131
AsCl3 Arsenous trichloride rClAs 2.166 2.335 0.170
BrF3 Bromine trifluoride rFBr 1.721 1.895 0.174
BrF3 Bromine trifluoride rFBr 1.810 1.941 0.131
KF Potassium Fluoride rKF 2.171 2.310 0.138
FNO3 Fluorine nitrate rNO 1.507 1.665 0.158
BrF5 bromine pentafluoride rFBr 1.689 1.862 0.173
BrF5 bromine pentafluoride rFBr 1.774 1.904 0.130
IBr Iodine monobromide rBrI 2.469 2.711 0.242
CaBr2 Calcium dibromide rCaBr 2.616 2.834 0.218
PBr3 Phosphorus tribromide rPBr 2.220 2.447 0.227
SiBr4 Silicon tetrabromide rSiBr 2.183 2.338 0.155
ClF Chlorine monofluoride rFCl 1.628 1.786 0.158
ClF3 Chlorine trifluoride rFCl 1.597 1.867 0.270
ClF3 Chlorine trifluoride rFCl 1.697 1.904 0.208
HOCl hypochlorous acid rClO 1.697 1.871 0.173
ICl Iodine monochloride rClI 2.321 2.557 0.236
Cl2O Dichlorine monoxide rClO 1.696 1.872 0.176
SO2Cl2 Sulfuryl chloride rSCl 2.076 2.446 0.370
SO2Cl2 Sulfuryl chloride rSO 1.443 1.595 0.152
He2+ helium diatomic cation rHeHe 1.081 1.274 0.194
GeCl Germanium monochloride rClGe 2.164 2.291 0.128
CaBr Calcium monobromide rCaBr 2.594 2.872 0.278
ClSSCl Disulfur dichloride rSCl 2.057 2.358 0.301
ClSSCl Disulfur dichloride rSS 1.931 2.161 0.230
SiHCl3 Trichlorosilane rSiCl 2.020 2.174 0.154
NCl3 nitrogen trichloride rNCl 1.754 1.955 0.201
Cl3PO Phosphoryl chloride rPCl 1.989 2.268 0.279
Cl3PO Phosphoryl chloride rPO 1.455 1.570 0.115
SbCl3 Antimony Trichloride rSbCl 2.333 2.500 0.167
SiCl4 Silane, tetrachloro- rSiCl 2.019 2.163 0.144
PCl5 Phosphorus pentachloride rPCl 2.020 2.279 0.259
PCl5 Phosphorus pentachloride rPCl 2.124 2.366 0.242
O3 Ozone rOO 1.278 1.401 0.123
OClO Chlorine dioxide rClO 1.470 1.752 0.282
GeCl2 Germanium dichloride rClGe 2.186 2.295 0.109
NO- nitric oxide anion rNO 1.258 1.371 0.113
NHF2 difluoramine rNF 1.400 1.503 0.103
S8 Octasulfur rSS 2.059 2.308 0.249
SCl2 Sulfur dichloride rSCl 2.013 2.285 0.272
SiF+ silicon monofluoride cation rFSi 1.527 1.628 0.101
GeS Germanium monosulfide rSGe 2.012 2.123 0.111
LiK Lithium Potassium rLiK 3.270 3.386 0.116
GaP Gallium monophosphide rPGa 2.450 2.324 -0.126
GeSe Germanium monoselenide rGeSe 2.135 2.240 0.105
SiC2 Silicon dicarbide rCSi 1.836 1.938 0.102
SiP Silicon monophosphide rSiP 2.078 2.200 0.123
PO2 Phosphorus dioxide rPO 1.467 1.607 0.140
CaOH Calcium monohydroxide rOCa 1.976 2.098 0.122
P2 Phosphorus diatomic rPP 1.893 1.997 0.104
P4 Phosphorus tetramer rPP 2.210 2.465 0.255
Se2 Selenium diatomic rSeSe 2.166 2.348 0.182
As4 Arsenic tetramer rAsAs 2.435 2.620 0.185
NCl nitrogen monochloride rNCl 1.611 1.835 0.224
SiSe Silicon Monoselenide rSiSe 2.058 2.173 0.115
AlS Aluminum sulfide rAlS 2.029 2.141 0.112
PS phosphorus sulfide rPS 1.900 2.064 0.164
ClOOCl Dichlorine dioxide rOCl 1.704 1.996 0.291
SiS silicon monosulfide rSiS 1.929 2.048 0.119
Ar2+ Argon diatomic cation rArAr 2.320 2.743 0.423
S3 Sulfur trimer rSS 1.917 2.169 0.252
ClNO2 Nitryl chloride rNCl 1.840 2.075 0.235
P2H4 Diphosphine rPP 2.219 2.435 0.216
GeBr4 Germanium tetrabromide rGeBr 2.272 2.384 0.112
TeO Tellurium monoxide rOTe 1.825 1.949 0.124
H2S2 Disulfane rSS 2.056 2.324 0.268
SiH3Br bromosilane rSiBr 2.210 2.368 0.158
SiH3Cl chlorosilane rSiCl 2.051 2.213 0.162
SiI4 silicon tetraiodide rSiI 2.432 2.610 0.178
F3PO Phosphoryl fluoride rFP 1.524 1.640 0.116
F3PO Phosphoryl fluoride rPO 1.436 1.546 0.110
CuF Copper monofluoride rCuF 1.745 1.600 -0.145
CuH Copper monohydride rCuH 1.463 1.796 0.333
HOBr Hypobromous acid rBrO 1.834 1.954 0.120
SiCl2 Dichlorosilylene rSiCl 2.076 2.256 0.180
HSiBr monobromosilylene rSiBr 2.237 2.424 0.187
AlCl Aluminum monochloride rAlCl 2.130 2.285 0.155
ClF5 chlorinepentafluoride rFCl 1.650 1.881 0.231
FSSF Difluorodisulfane rSS 1.890 2.247 0.357
FSSF Difluorodisulfane rFS 1.635 1.763 0.128
XeF2 Xenon difluoride rFXe 1.974 2.207 0.233
SOF4 Sulfur tetrafluoride oxide rFS 1.539 1.715 0.176
SOF4 Sulfur tetrafluoride oxide rSO 1.409 1.565 0.156
SOF4 Sulfur tetrafluoride oxide rFS 1.596 1.738 0.142
XeF4 Xenon tetrafluoride rFXe 1.935 2.134 0.199
KrF2 Krypton difluoride rFKr 1.875 2.080 0.205
SF5Cl sulfur chloropentafluoride rSCl 2.030 2.430 0.400
SF5Cl sulfur chloropentafluoride rFS 1.576 1.721 0.145
N2F2 (Z)-Difluorodiazene rNF 1.384 1.494 0.110
SF2 sulfur difluoride rSF 1.587 1.735 0.148
CaF Calcium monofluoride rFCa 1.967 2.139 0.172
SO Sulfur monoxide rSO 1.481 1.652 0.171
SO Sulfur monoxide rOS 1.500 1.654 0.154
SO+ sulfur monoxide cation rOS 1.424 1.574 0.150
Al2Cl6 Aluminum, di-μ-chlorotetrachlorodi- rAlCl 2.040 2.403 0.363
HSSSH trisulfane rHS 1.344 2.314 0.971
HSSSH trisulfane rSS 2.053 2.315 0.262
HSSSH trisulfane rSS 2.054 2.314 0.261
F3NO Nitrogen trifluoride oxide rNF 1.431 1.532 0.101
BrCl Bromine monochloride rClBr 2.136 2.377 0.241
BrF Bromine monofluoride rFBr 1.759 1.875 0.116
PF2 Phosphorus difluoride rPF 1.579 1.691 0.112
IF Iodine monofluoride rFI 1.910 2.038 0.129
HSiCl Chlorosilylene rSiCl 2.067 2.263 0.196
SiCl Clorosilylidyne rSiCl 2.061 2.251 0.190
NBr nitrogen monobromide rNBr 1.765 1.917 0.152
NH2SH Thiohydroxylamine rNS 1.719 1.883 0.164
NH2SH Thiohydroxylamine rNS 1.705 1.813 0.108
HOI Hypoiodous acid rOI 1.994 2.132 0.138
PO- phosphorus monoxide anion rOP 1.540 1.693 0.153
PO Phosphorus monoxide rPO 1.476 1.599 0.123
CaH Calcium monohydride rCaH 2.003 2.196 0.194
SeCl2 Selenium Dichloride rClSe 2.157 2.366 0.209
IO Iodine monoxide rIO 1.868 2.048 0.180
H2O3 Hydrogen trioxide rOO 1.428 1.534 0.106
SiBr Silicon monobromide rSiBr 2.209 2.406 0.197
SiBr+ Silicon monobromide cation rSiBr 2.095 2.273 0.177
MgCl magnesium monochloride rMgCl 2.199 2.312 0.113
ClO Monochlorine monoxide rClO 1.596 1.785 0.189
SCl sulfur monochloride rSCl 1.975 2.243 0.268
FOO Dioxygen monofluoride radical rOO 1.200 1.347 0.147
CaCl calcium monochloride rClCa 2.437 2.700 0.263
BrO Bromine monoxide rOBr 1.718 1.862 0.144
BrO+ Bromine monoxide cation rOBr 1.635 1.761 0.126
PF+ phosphorus monofluoride cation rFP 1.500 1.633 0.133
PF phosphorus monofluoride rFP 1.593 1.701 0.108
SF Monosulfur monofluoride rSF 1.599 1.733 0.133
C3H5Cl 1-chloro-1-propene(Z) rCCl 1.735 1.870 0.135
C3H5Cl 1-chloro-1-propene(E) rCCl 1.728 1.865 0.137
PCl phosphorus chloride rPCl 2.018 2.254 0.237
FSN Thiazyl fluoride rFS 1.643 1.827 0.184
FSN Thiazyl fluoride rNS 1.448 1.574 0.126
BH3PH3 borane phosphine rBP 1.937 2.053 0.116
S4 Sulfur tetramer rSS 2.155 2.783 0.628
S4 Sulfur tetramer rSS 1.898 2.113 0.215
BBr Boron monobromide rBBr 1.888 1.995 0.107
CaS Calcium sulfide rSCa 2.318 2.636 0.319
BCl boron monochloride rBCl 1.719 1.820 0.101
SSO Disulfur monoxide rSS 1.884 2.183 0.299
SSO Disulfur monoxide rSO 1.456 1.632 0.175
OPCl Phosphorus oxychloride rPCl 2.059 2.361 0.302
OPCl Phosphorus oxychloride rPO 1.462 1.572 0.110
AlBr Aluminum monobromide rAlBr 2.295 2.430 0.135
S2 Sulfur diatomic rSS 1.889 2.116 0.227
S2+ sulfur diatomic cation rSS 1.825 2.027 0.202
S2N2 Disulfur dinitride rNS 1.642 1.859 0.218
K2 Potassium diatomic rKK 3.905 4.007 0.102
Mg2 Magnesium diatomic rMgMg 3.891 4.114 0.223
AlI Aluminum monoiodide rAlI 2.537 2.705 0.168
ClOF3 Chlorine trifluoride oxide rFCl 1.603 1.918 0.315
ClOF3 Chlorine trifluoride oxide rOCl 1.405 1.663 0.258
ClOF3 Chlorine trifluoride oxide rFCl 1.713 1.939 0.226
C4H5NO 3-Methylisoxazole rNO 1.403 1.524 0.121
Al2 Aluminum diatomic rAlAl 2.701 2.555 -0.146
Si2H2 disilyne rSiSi 2.215 2.354 0.139
ClS2 Sulfur chloride rSCl 2.071 2.395 0.324
ClS2 Sulfur chloride rSS 1.906 2.117 0.211
HOSH hydrogen thioperoxide rSO 1.662 1.828 0.167
SFCl Sulfur chloride fluoride rSCl 1.994 2.311 0.317
SFCl Sulfur chloride fluoride rFS 1.606 1.732 0.126
CaC Calcium monocarbide rCCa 2.302 2.533 0.232
ZnCN Zinc monocyanide rCZn 1.950 1.809 -0.141
314 molecules.