National Institute of Standards and Technology

Computational Chemistry Comparison and Benchmark DataBase
Release 22	May 2022
NIST Standard Reference Database 101

I	Introduction
II	Experimental data
III	Calculated data
IV	Data comparisons
V	Cost comparisons
VI	Input and output files
VII	Tutorials and Units
VIII	Links to other sites
IX	Feedback
X	Older CCCBDB versions
XII	Geometries
XIII	Vibrations
XIV	Reaction data
XV	Entropy data
XVI	Bibliographic data
XVII	Ion data
XVIII	Bad calculations
XIX	Index of properties
XX	H-bond dimers
XXI	Oddities

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II.B.3. (XII.A.3.)

List of experimental bond lengths for bond type rC=O

Bond lengths in Å.
Click on an entry for more experimental geometry data.

bond type	Species	Name	Length	Comment
rC=O	CO+	carbon monoxide cation	1.115	re
rC=O	BH3CO	Borane carbonyl	1.135
rC=O	HOCO+	Hydrocarboxyl cation	1.140
rC=O	C3O2	Carbon suboxide	1.146	from crystal structure
rC=O	OCSe	Carbonyl selenide	1.159	r0
rC=O	OCS	Carbonyl sulfide	1.160
rC=O	CH2CO	Ketene	1.162	rs structure
rC=O	CO2	Carbon dioxide	1.162
rC=O	HNCO	Isocyanic acid	1.164	derived from earlier work, mistype in 1997BRO/BER:9764
rC=O	C3H4O	Methylketene	1.171
rC=O	COBr2	Carbonic dibromide	1.172	r0
rC=O	CF2O	Carbonic difluoride	1.174
rC=O	CCl2O	Phosgene	1.177	re value
rC=O	FCO	Carbonyl fluoride	1.180
rC=O	CH3COF	Acetyl fluoride	1.181
rC=O	HFCO	formyl fluoride	1.181
rC=O	ClCOClCO	Oxalyl chloride	1.182
rC=O	CHOOCHO	diformyl ether	1.184	rs
rC=O	CH3COCl	Acetyl Chloride	1.187	rg
rC=O	C3H2O3	vinylene carbonate	1.191
rC=O	C3H4O	Cyclopropanone	1.191
rC=O	C4H2O3	Maleic Anhydride	1.192
rC=O	CF3COOH	trifluoroacetic acid	1.192	ra
rC=O	CH3CH(NH2)COOH	Alanine	1.192
rC=O	CHOOCHO	diformyl ether	1.195
rC=O	HCO	Formyl radical	1.198
rC=O	CH3OCHO	methyl formate	1.200
rC=O	HCOOH	Formic acid	1.202
rC=O	C4H6O	Cyclobutanone	1.202
rC=O	C4H8O2	Ethyl acetate	1.203	rg
rC=O	C2H2O4	Oxalic Acid	1.205
rC=O	H2CO	Formaldehyde	1.205
rC=O	CHOCH(CH3)CH3	Propanal, 2-methyl-	1.206
rC=O	CH2ClCHO	chloroacetaldehyde	1.206
rC=O	H2NCH2COOH	Glycine	1.207
rC=O	C6H12O	hexanal	1.208
rC=O	C5H4O2	4-Cyclopentene-1,3-dione	1.208
rC=O	HOCO+	Hydrocarboxyl cation	1.209
rC=O	CHONH2	formamide	1.210
rC=O	HOCH2COOH	Hydroxyacetic acid	1.210
rC=O	CH3CH2CHO	Propanal	1.210
rC=O	C2H2O2	Ethanedial	1.212
rC=O	CH3COOH	Acetic acid	1.212
rC=O	C2H2CO	cyclopropenone	1.212
rC=O	CH2CHCHO	Acrolein	1.213
rC=O	CH3COCH3	Acetone	1.214
rC=O	HCCCHO	2-propynal	1.214
rC=O	C4H6O2	2,3-Butanedione	1.214
rC=O	C5H8O	Cyclopentanone	1.215	!assumed
rC=O	C4H4N2O2	Uracil	1.215
rC=O	CH2CHCHO	Acrolein	1.215
rC=O	CH3CHO	Acetaldehyde	1.216
rC=O	C5H10O	2-Butanone, 3-methyl-	1.217
rC=O	C2H4O4	Formic acid dimer	1.217
rC=O	CH3COCH2CH3	2-Butanone	1.218
rC=O	HCONHCH3	N-methylformamide	1.219
rC=O	CHOCHCHCH3	2-Butenal	1.219	!assumed
rC=O	CH3CONH2	Acetamide	1.220
rC=O	NH2CONH2	Urea	1.221
rC=O	C3H7NO	dimethylformamide	1.224
rC=O	C5H8O	Methyl cyclopropyl ketone	1.225
rC=O	C6H10O	cyclohexanone	1.229
rC=O	C4H4N2O2	Uracil	1.245
rC=O	H2COO	Dioxymethyl radical	1.272
Average			1.198	±0.027
Min			1.115
Max			1.272