CCCBDB listing of experimental data page 2

Other names
Bicyclo[5.3.0]decapentaene; Cyclopentacycloheptene; Bicyclo(5.3.0)-1,3,5,7,9-decapentaene; azulene;

INChI	INChIKey	SMILES	IUPAC name
InChI=1S/C10H8/c1-2-5-9-7-4-8-10(9)6-3-1/h1-8H	CUFNKYGDVFVPHO-UHFFFAOYSA-N	C12=CC=CC=CC1=CC=C2	azulene

State	Conformation
¹A₁	C2V

Enthalpy of formation (Hfg), Entropy, Integrated heat capacity (0 K to 298.15 K) (HH), Heat Capacity (Cp)

Property	Value	units	Reference
Hfg(298.15K)	308.00	kJ mol^-1	webbook
Hfg(0K)		kJ mol^-1	webbook
Heat Capacity (298.15K)	128.41	J K^-1 mol^-1	webbook

Information can also be found for this species in the NIST Chemistry Webbook

Vibrational levels (cm^-1) vibrations

Mode Number	Symmetry	Frequency			Intensity			Comment	Description
Mode Number	Symmetry	Fundamental(cm^-1)	Harmonic(cm^-1)	Reference	(km mol^-1)	unc.	Reference	Comment	Description

Calculated vibrational frequencies for C₁₀H₈ (Azulene).

Rotational Constants (cm^-1)

See section I.F.4 to change rotational constant units

A	B	C	reference	comment
0.09480	0.04186	0.02904	2007Tho/The:1309-1314

Calculated rotational constants for C₁₀H₈ (Azulene).

Product of moments of inertia
4.15691E+07	amu³Å⁶		1.90343726649312E-112	gm³ cm⁶

Geometric Data
picture of Azulene

Point Group C_2v

Internal coordinates
distances (r) in Å, angles (a) in degrees, dihedrals (d) in degrees

Description	Value	unc.	Connectivity				Reference	Comment
Description	Value	unc.	Atom 1	Atom 2	Atom 3	Atom 4	Reference	Comment
rCC	1.405	0.001	2	9			2005Hub/Gra:1395-1409	re
rCC	1.414		7	9			2005Hub/Gra:1395-1409	re
rCC	1.484		7	8			2005Hub/Gra:1395-1409	re
rCC	1.377		5	7			2005Hub/Gra:1395-1409	re
rCC	1.407		3	5			2005Hub/Gra:1395-1409
rCC	1.398		1	3			2005Hub/Gra:1395-1409	re
rCH	1.080		9	17			2005Hub/Gra:1395-1409	re
rCH	1.081		2	12			2005Hub/Gra:1395-1409
rCH	1.083		5	15			2005Hub/Gra:1395-1409	re
rCH	1.084		4	14			2005Hub/Gra:1395-1409	re
rCH	1.081		1	11			2005Hub/Gra:1395-1409	re
aCCC	109.65		9	2	10		2005Hub/Gra:1395-1409	re
aCCC	108.42		2	9	7		2005Hub/Gra:1395-1409
aCCC	106.76		7	8	10		2005Hub/Gra:1395-1409
aCCC	128.35		5	7	8		2005Hub/Gra:1395-1409
aCCC	128.07		3	5	7		2005Hub/Gra:1395-1409
aCCC	128.67		1	3	5		2005Hub/Gra:1395-1409
aCCC	129.83		3	1	4		2005Hub/Gra:1395-1409
aCCH	125.09		7	9	17		2005Hub/Gra:1395-1409
aCCH	125.17		9	2	12		2005Hub/Gra:1395-1409
aCCH	116.47		7	5	15		2005Hub/Gra:1395-1409
aCCH	115.46		1	3	13		2005Hub/Gra:1395-1409
aCCH	115.08		3	1	11		2005Hub/Gra:1395-1409

Cartesians

Atom	y (Å)	z (Å)
C1	0.0000	-2.5078
C2	0.0000	2.6970
C3	1.2661	-1.9151
C4	-1.2661	-1.9151
C5	1.5965	-0.5476
C6	-1.5965	-0.5476
C7	0.7420	0.5324
C8	-0.7420	0.5324
C9	1.1497	1.8867
C10	-1.1497	1.8867
H11	0.0000	-3.5893
H12	0.0000	3.7775
H13	2.1025	-2.6040
H14	-2.1025	-2.6040
H15	2.6560	-0.3242
H16	-2.6560	-0.3242
H17	2.1745	2.2261
H18	-2.1745	2.2261

Atom - Atom Distances bond lengths

Distances in Å

	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10	H11	H12	H13	H14	H15	H16	H17	H18
C1		5.2048	1.3980	1.3980	2.5281	2.5281	3.1294	3.1294	4.5424	4.5424	1.0815	6.2853	2.1047	2.1047	3.4384	3.4384	5.2094	5.2094
C2	5.2048		4.7827	4.7827	3.6161	3.6161	2.2882	2.2882	1.4066	1.4066	6.2863	1.0805	5.7027	5.7027	4.0227	4.0227	2.2249	2.2249
C3	1.3980	4.7827		2.5322	1.4068	3.1725	2.5030	3.1659	3.8036	4.5044	2.0990	5.8317	1.0836	3.4383	2.1125	4.2325	4.2397	5.3840
C4	1.3980	4.7827	2.5322		3.1725	1.4068	3.1659	2.5030	4.5044	3.8036	2.0990	5.8317	3.4383	1.0836	4.2325	2.1125	5.3840	4.2397
C5	2.5281	3.6161	1.4068	3.1725		3.1930	1.3772	2.5758	2.4750	3.6698	3.4352	4.6103	2.1177	4.2322	1.0828	4.2584	2.8333	4.6812
C6	2.5281	3.6161	3.1725	1.4068	3.1930		2.5758	1.3772	3.6698	2.4750	3.4352	4.6103	4.2322	2.1177	4.2584	1.0828	4.6812	2.8333
C7	3.1294	2.2882	2.5030	3.1659	1.3772	2.5758		1.4840	1.4143	2.3265	4.1880	3.3288	3.4188	4.2342	2.0969	3.5043	2.2183	3.3726
C8	3.1294	2.2882	3.1659	2.5030	2.5758	1.3772	1.4840		2.3265	1.4143	4.1880	3.3288	4.2342	3.4188	3.5043	2.0969	3.3726	2.2183
C9	4.5424	1.4066	3.8036	4.5044	2.4750	3.6698	1.4143	2.3265		2.2994	5.5954	2.2129	4.5907	5.5447	2.6753	4.4013	1.0795	3.3415
C10	4.5424	1.4066	4.5044	3.8036	3.6698	2.4750	2.3265	1.4143	2.2994		5.5954	2.2129	5.5447	4.5907	4.4013	2.6753	3.3415	1.0795
H11	1.0815	6.2863	2.0990	2.0990	3.4352	3.4352	4.1880	4.1880	5.5954	5.5954		7.3668	2.3219	2.3219	4.2089	4.2089	6.2086	6.2086
H12	6.2853	1.0805	5.8317	5.8317	4.6103	4.6103	3.3288	3.3288	2.2129	2.2129	7.3668		6.7189	6.7189	4.8865	4.8865	2.6712	2.6712
H13	2.1047	5.7027	1.0836	3.4383	2.1177	4.2322	3.4188	4.2342	4.5907	5.5447	2.3219	6.7189		4.2050	2.3460	5.2764	4.8306	6.4516
H14	2.1047	5.7027	3.4383	1.0836	4.2322	2.1177	4.2342	3.4188	5.5447	4.5907	2.3219	6.7189	4.2050		5.2764	2.3460	6.4516	4.8306
H15	3.4384	4.0227	2.1125	4.2325	1.0828	4.2584	2.0969	3.5043	2.6753	4.4013	4.2089	4.8865	2.3460	5.2764		5.3120	2.5954	5.4624
H16	3.4384	4.0227	4.2325	2.1125	4.2584	1.0828	3.5043	2.0969	4.4013	2.6753	4.2089	4.8865	5.2764	2.3460	5.3120		5.4624	2.5954
H17	5.2094	2.2249	4.2397	5.3840	2.8333	4.6812	2.2183	3.3726	1.0795	3.3415	6.2086	2.6712	4.8306	6.4516	2.5954	5.4624		4.3490
H18	5.2094	2.2249	5.3840	4.2397	4.6812	2.8333	3.3726	2.2183	3.3415	1.0795	6.2086	2.6712	6.4516	4.8306	5.4624	2.5954	4.3490

Calculated geometries for C₁₀H₈ (Azulene).

Experimental Bond Angles (degrees) from cartesians

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C3	C5	128.669	C1	C3	H13	115.438
C1	C4	C6	128.669	C1	C4	H14	115.438
C2	C9	C7	108.422	C2	C9	H17	126.500
C2	C10	C8	108.422	C2	C10	H18	126.500
C3	C1	C4	129.829	C3	C1	H11	115.086
C3	C5	C7	128.066	C3	C5	H15	115.490
C4	C1	H11	115.086	C4	C6	C8	128.066
C4	C6	H16	115.490	C5	C3	H13	115.894
C5	C7	C8	128.351	C5	C7	C9	124.895
C6	C4	H14	115.894	C6	C8	C7	128.351
C6	C8	C10	124.895	C7	C5	H15	116.445
C7	C8	C10	106.754	C7	C9	H17	125.078
C8	C6	H16	116.445	C8	C7	C9	106.754
C8	C10	H18	125.078	C9	C2	C10	109.648
C9	C2	H12	125.176	C10	C2	H12	125.176

Bond descriptions

Examples: C-C single bond, C=C, double bond, C#C triple bond, C:C aromatic bond

Bond Type	Count
C:C	11
H-C	8

Connectivity

Atom 1	Atom 2
C1	C3
C1	C4
C1	H11
C2	C9
C2	C10
C2	H12
C3	C5
C3	H13
C4	C6
C4	H14
C5	C7
C5	H15
C6	C8
C6	H16
C7	C8
C7	C9
C8	C10
C9	H17
C10	H18

Electronic energy levels (cm^-1)

Energy (cm^-1)	Degeneracy	reference	description
0	1		¹A₁

Dipole, Quadrupole and Polarizability
Electric dipole moment dipole

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	¹A₁	C_2v	True	0.000	0.000	0.882	0.882	2005Hub/Gra:1395-1409	MW ± 0.0024 D μ₀	C_2v	1	2
1	2	¹A^'	C_s	False							C_s	2	3

Experimental dipole measurement abbreviations: MW microwave; DT Dielectric with Temperature variation; DR Indirect (usually an upper limit); MB Molecular beam
Calculated electric dipole moments for C₁₀H₈ (Azulene).
Electric quadrupole moment

State	Config	State description	Conf description	Exp. min.	Quadrupole (D Å)			Reference	comment	Point Group	Components
State	Config	State description	Conf description	Exp. min.	xx	yy	zz	Reference	comment	Point Group	dipole	quadrupole
1	1	¹A₁	C_2v	True						C_2v	1	2
1	2	¹A^'	C_s	False						C_s	2	3

Calculated electric quadrupole moments for C₁₀H₈ (Azulene).
Electric dipole polarizability (Å³)

alpha	unc.	Reference
15.520		1998Gus/Rui:163

Calculated electric dipole polarizability for C₁₀H₈ (Azulene).

References
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squib	reference	DOI
1998Gus/Rui:163	M Gussoni, R Rui, G Zerbi "Electronic and relaxation contribution to linear molecular polarizability. An analysis of the experimental values" J. Mol. Struct. 447 (1998) 163-215	10.1016/S0022-2860(97)00292-5
2005Hub/Gra:1395-1409	S Huber, G Grassi, A Bauder "Structure and symmetry of azulene as determined from microwave spectra of isotopomers" Molecular Physics, 103:10, 1395-1409, 2005	10.1080/00268970500038451
2007Tho/The:1309-1314	S. Thorwirth, P Theule, CA Gottlieb, MC McCarthy, P Thaddeus "ROTATIONAL SPECTRA OF SMALL PAHs: ACENAPHTHYLENE, AZULENE, AND FLUORENE" Astrophysical Journal 662 1309 - 1314, 2007	10.1086/518026
webbook	NIST Chemistry Webbook (http://webbook.nist.gov/chemistry)	10.18434/T4D303

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You are here: Experimental > One molecule all properties

Atom 1	Atom 2
C1	C3
C1	C4
C1	H11
C2	C9
C2	C10
C2	H12
C3	C5
C3	H13
C4	C6
C4	H14
C5	C7
C5	H15
C6	C8
C6	H16
C7	C8
C7	C9
C8	C10
C9	H17
C10	H18

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Atom 1	Atom 2
C1	C3
C1	C4
C1	H11
C2	C9
C2	C10
C2	H12
C3	C5
C3	H13
C4	C6
C4	H14
C5	C7
C5	H15
C6	C8
C6	H16
C7	C8
C7	C9
C8	C10
C9	H17
C10	H18

Experimental data for C10H8 (Azulene)

Experimental data for C₁₀H₈ (Azulene)

Atom 1	Atom 2
C1	C3
C1	C4
C1	H11
C2	C9
C2	C10
C2	H12
C3	C5
C3	H13
C4	C6
C4	H14
C5	C7
C5	H15
C6	C8
C6	H16
C7	C8
C7	C9
C8	C10
C9	H17
C10	H18