CCCBDB listing of experimental data page 2

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Property	Value	Uncertainty	units	Reference
Hfg(298.15K)	132.90	0.60	kJ mol^-1	1987JIM/ROU
Hfg(0K)		0.60	kJ mol^-1	1987JIM/ROU
Entropy (298.15K)			J K^-1 mol^-1
Integrated Heat Capacity (0 to 298.15K)			kJ mol^-1

Mode Number	Symmetry	Frequency			Intensity			Comment	Description
Mode Number	Symmetry	Fundamental(cm^-1)	Harmonic(cm^-1)	Reference	(km mol^-1)	unc.	Reference	Comment	Description
1	A'	3517		1999Bil/End:157
2	A'	3143		1999Bil/End:157
3	A'	3123		1999Bil/End:157
4	A'	3110		1999Bil/End:157
5	A'	1448		1999Bil/End:157
6	A'	1404		1999Bil/End:157
7	A'	1328		1999Bil/End:157
8	A'	1265		1999Bil/End:157
9	A'	1188		1999Bil/End:157
10	A'	1098		1999Bil/End:157
11	A'	1062		1999Bil/End:157
12	A'	1013		1999Bil/End:157
13	A'	988		1999Bil/End:157
14	A'	923		1999Bil/End:157
15	A'	898		1999Bil/End:157
16	A"	831		1999Bil/End:157
17	A"	758		1999Bil/End:157
18	A"	674		1999Bil/End:157
19	A"	663		1999Bil/End:157
20	A"	621		1999Bil/End:157
21	A"	539		1999Bil/End:157

Description	Value	unc.	Connectivity				Reference	Comment
Description	Value	unc.	Atom 1	Atom 2	Atom 3	Atom 4	Reference	Comment
rNH	0.998		2	9			1987Kuchitsu(II/15)
rCH	1.079		7	8			1987Kuchitsu(II/15)	in between N and N
rCH	1.078		5	6			1987Kuchitsu(II/15)	next to N w/o H
rCH	1.079		3	4			1987Kuchitsu(II/15)	next to N with H
rCN	1.364		8	9			1987Kuchitsu(II/15)	to C inbetween 2 N
rCN	1.314		1	8			1987Kuchitsu(II/15)
rCN	1.382		1	5			1987Kuchitsu(II/15)	from N w/o H
rCC	1.364		3	5			1987Kuchitsu(II/15)
rCN	1.377		3	9			1987Kuchitsu(II/15)	from =C to N with H
aNCN	111.99		1	8	9		1987Kuchitsu(II/15)
aCNC	104.93		5	1	8		1987Kuchitsu(II/15)
aCCN	110.69		1	5	3		1987Kuchitsu(II/15)	from N w/o H
aCCN	105.48		5	3	9		1987Kuchitsu(II/15)	from N with H
aCNC	106.9		3	9	8		1987Kuchitsu(II/15)

Atom	x (Å)	y (Å)
N1	-0.7475	-0.9823
H2	-0.0089	2.1061
C3	1.1135	0.2980
H4	2.1470	0.6081
C5	0.6345	-0.9791
H6	1.2496	-1.8644
H7	-2.1094	0.6372
C8	-1.0890	0.2865
N9	0.0000	1.1081

	N1	H2	C3	H4	C5	H6	H7	C8	N9
N1		3.1755	2.2589	3.3026	1.3820	2.1832	2.1160	1.3140	2.2201
H2	3.1755		2.1281	2.6252	3.1516	4.1652	2.5631	2.1159	0.9980
C3	2.2589	2.1281		1.0790	1.3640	2.1667	3.2407	2.2025	1.3770
H4	3.3026	2.6252	1.0790		2.1924	2.6303	4.2564	3.2519	2.2044
C5	1.3820	3.1516	1.3640	2.1924		1.0780	3.1846	2.1383	2.1816
H6	2.1832	4.1652	2.1667	2.6303	1.0780		4.1882	3.1773	3.2245
H7	2.1160	2.5631	3.2407	4.2564	3.1846	4.1882		1.0790	2.1613
C8	1.3140	2.1159	2.2025	3.2519	2.1383	3.1773	1.0790		1.3641
N9	2.2201	0.9980	1.3770	2.2044	2.1816	3.2245	2.1613	1.3641

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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You are here: Experimental > One molecule all properties

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
N1	H2	H4	68.656	N1	H2	H7	41.585
N1	C3	C5	34.915	N1	C3	C8	34.229
H2	N1	C3	42.023	H2	N1	H6	100.381
H2	H4	C5	81.175	C3	N1	H6	58.358
C3	C5	H4	23.060	C3	C5	N9	37.467
H4	H2	H7	110.242	H4	C5	N9	60.527
C5	C3	C8	69.144

State	Config	State description	Conf description	Exp. min.	Dipole (Debye)				Reference	comment	Point Group	Components
State	Config	State description	Conf description	Exp. min.	x	y	z	total	Reference	comment	Point Group	dipole	quadrupole
1	1	¹A^'	C_s	True	3.603	0.680		3.667	1982Chr/Gri:1378	x=a y=b μ₀	C_s	2	3

squib	reference	DOI
1982Chr/Gri:1378	D Christen, JH Griffiths, J Sheridan "The Microwave Spectrum of Imidazole; Complete Structure and the Electron Distribution from Nuclear Quardupole Coupling Tensors and Dipole Moment Orientation" Z. Naturforsch. 37a, 1378-1385 (1982)	10.1515/zna-1981-1220
1987JIM/ROU	Jiminez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of N-heterocyclic compounds. I. Enthalpies of combustion, vapour pressures and enthalpies of sublimation, and enthalpies of formation of pyrazole, imidazole, indazole, and benzimidazole, J. Chem. Thermodyn., 1987, 19, 985-992. [all data]	10.1016/0021-9614(87)90045-0
1987Kuchitsu(II/15)	Kuchitsu (ed.), Landolt-Bornstein: Group II: Atomic and Molecular Physics Volume 15: Structure Data of Free Polyatomic Molecules. Springer-Verlag, Berlin, 1987.
1990Mil:8533	KJ Miller "Additivity Methods in Molecular Polarizability" J. Am. Chem. Soc. 1990, 112, 8533-8542	10.1021/ja00179a044
1999Bil/End:157	Billes, Endredi, and Jalsovsky. Vibrational spectroscopy of diazoles. J. Mol. Struct. (Theochem) Vol. 465. pgs. 157-172.	10.1016/S0166-1280(98)00326-1
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)	10.18434/T4D303

Bond Type	Count
H-C	3
H-N	1
C=C	1
C-N	3
C=N	1

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Experimental data for C3H4N2 (1H-Imidazole)

Experimental data for C₃H₄N₂ (1H-Imidazole)