CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	no	C2H	¹A_g
1	2	yes	C2	¹A
1	3	no	CI	¹A_g

Conformer 1 (C2H)

Jump to S1C2 S1C3

Energy calculated at B3LYP/STO-3G

	hartrees
Energy at 0K	-302.467177
Energy at 298.15K
Nuclear repulsion energy	219.094879

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at B3LYP/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3492	3117	0.00
2	A_g	3305	2949	0.00
3	A_g	1812	1617	0.00
4	A_g	1650	1472	0.00
5	A_g	1527	1363	0.00
6	A_g	1276	1139	0.00
7	A_g	1057	944	0.00
8	A_g	679	606	0.00
9	A_g	514	459	0.00
10	A_g	327	292	0.00
11	A_u	3465	3092	0.22
12	A_u	1649	1472	10.98
13	A_u	1048	936	7.42
14	A_u	333	297	0.69
15	A_u	83	74	1.09
16	A_u	10i	9i	2.30
17	B_g	3465	3092	0.00
18	B_g	1651	1473	0.00
19	B_g	1110	990	0.00
20	B_g	608	542	0.00
21	B_g	50	45	0.00
22	B_u	3492	3117	0.90
23	B_u	3305	2949	3.46
24	B_u	1814	1619	22.86
25	B_u	1651	1473	14.95
26	B_u	1526	1361	12.62
27	B_u	1161	1036	89.01
28	B_u	958	855	23.07
29	B_u	513	458	20.48
30	B_u	193	172	5.08

Unscaled Zero Point Vibrational Energy (zpe) 21851.5 cm^-1
Scaled (by 0.8924) Zero Point Vibrational Energy (zpe) 19500.2 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at B3LYP/STO-3G

A	B	C
0.16307	0.10651	0.06605

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

Geometric Data calculated at B3LYP/STO-3G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.097	0.792	0.000
C2	0.097	-0.792	0.000
C3	1.239	1.602	0.000
C4	-1.239	-1.602	0.000
O5	-1.239	1.312	0.000
O6	1.239	-1.312	0.000
H7	1.030	2.682	0.000
H8	-1.030	-2.682	0.000
H9	1.833	1.342	0.891
H10	1.833	1.342	-0.891
H11	-1.833	-1.342	0.891
H12	-1.833	-1.342	-0.891

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5963	1.5616	2.6524	1.2544	2.4921	2.2000	3.5972	2.1952	2.1952	2.8915	2.8915
C2	1.5963		2.6524	1.5616	2.4921	1.2544	3.5972	2.2000	2.8915	2.8915	2.1952	2.1952
C3	1.5616	2.6524		4.0496	2.4940	2.9137	1.0999	4.8473	1.1020	1.1020	4.3463	4.3463
C4	2.6524	1.5616	4.0496		2.9137	2.4940	4.8473	1.0999	4.3463	4.3463	1.1020	1.1020
O5	1.2544	2.4921	2.4940	2.9137		3.6083	2.6501	3.9991	3.1981	3.1981	2.8614	2.8614
O6	2.4921	1.2544	2.9137	2.4940	3.6083		3.9991	2.6501	2.8614	2.8614	3.1981	3.1981
H7	2.2000	3.5972	1.0999	4.8473	2.6501	3.9991		5.7456	1.7984	1.7984	5.0177	5.0177
H8	3.5972	2.2000	4.8473	1.0999	3.9991	2.6501	5.7456		5.0177	5.0177	1.7984	1.7984
H9	2.1952	2.8915	1.1020	4.3463	3.1981	2.8614	1.7984	5.0177		1.7816	4.5428	4.8796
H10	2.1952	2.8915	1.1020	4.3463	3.1981	2.8614	1.7984	5.0177	1.7816		4.8796	4.5428
H11	2.8915	2.1952	4.3463	1.1020	2.8614	3.1981	5.0177	1.7984	4.5428	4.8796		1.7816
H12	2.8915	2.1952	4.3463	1.1020	2.8614	3.1981	5.0177	1.7984	4.8796	4.5428	1.7816

picture of 2,3-Butanedione state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	114.258	C1	C2	O6	121.438
C1	C3	H7	110.298	C1	C3	H9	109.799
C1	C3	H10	109.799	C2	C1	C3	114.258
C2	C1	O5	121.438	C2	C4	H8	110.298
C2	C4	H11	109.799	C2	C4	H12	109.799
C3	C1	O5	124.304	C4	C2	O6	124.304
H7	C3	H9	109.520	H7	C3	H10	109.520
H8	C4	H11	109.520	H8	C4	H12	109.520
H9	C3	H10	107.865	H11	C4	H12	107.865

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/STO-3G Charges (e)

Number	Element	Mulliken
1	C	0.138
2	C	0.138
3	C	-0.241
4	C	-0.241
5	O	-0.168
6	O	-0.168
7	H	0.088
8	H	0.088
9	H	0.091
10	H	0.091
11	H	0.091
12	H	0.091

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	0.000	0.000
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-34.807	4.512	0.000
y	4.512	-33.431	0.000
z	0.000	0.000	-30.975

Traceless
	x	y	z
x	-2.604	4.512	0.000
y	4.512	-0.541	0.000
z	0.000	0.000	3.145

Polar
3z²-r²	6.289
x²-y²	-1.375
xy	4.512
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	4.851	-0.218	0.000
y	-0.218	4.421	0.000
z	0.000	0.000	2.271

<r²> (average value of r²) Å²

<r²>	169.895
(<r²>)^1/2	13.034

Conformer 2 (C2)

Jump to S1C1 S1C3

Energy calculated at B3LYP/STO-3G

	hartrees
Energy at 0K	-302.467273
Energy at 298.15K	-302.472701
Nuclear repulsion energy	219.443705

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at B3LYP/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3482	3107	0.00
2	A	3468	3095	0.13
3	A	3303	2947	0.00
4	A	1803	1609	0.00
5	A	1662	1483	10.14
6	A	1646	1469	0.00
7	A	1512	1350	0.00
8	A	1264	1128	0.00
9	A	1053	939	8.00
10	A	1046	933	0.00
11	A	682	609	0.00
12	A	532	475	0.00
13	A	339	302	1.42
14	A	325	290	0.00
15	A	114	102	1.10
16	A	23	20	2.85
17	B	3482	3107	8.24
18	B	3468	3095	0.00
19	B	3303	2947	1.48
20	B	1811	1616	19.41
21	B	1663	1484	0.00
22	B	1645	1468	9.43
23	B	1511	1348	24.40
24	B	1154	1029	120.80
25	B	1113	993	0.00
26	B	975	870	10.32
27	B	613	547	0.00
28	B	521	465	17.01
29	B	205	183	8.79
30	B	76	68	0.00

Unscaled Zero Point Vibrational Energy (zpe) 21895.0 cm^-1
Scaled (by 0.8924) Zero Point Vibrational Energy (zpe) 19539.1 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at B3LYP/STO-3G

A	B	C
0.16245	0.10726	0.06624

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

Geometric Data calculated at B3LYP/STO-3G

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.096	0.793	-0.000
C2	-0.096	-0.793	-0.000
C3	-1.243	1.595	0.000
C4	1.243	-1.595	0.000
O5	1.243	1.304	-0.000
O6	-1.243	-1.304	-0.000
H7	-1.305	2.236	0.894
H8	1.305	-2.236	0.894
H9	-1.305	2.237	-0.893
H10	-2.078	0.877	-0.000
H11	1.305	-2.237	-0.893
H12	2.078	-0.877	-0.000

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5985	1.5602	2.6491	1.2551	2.4883	2.2009	3.3820	2.2010	2.1753	3.3825	2.5919
C2	1.5985		2.6491	1.5602	2.4883	1.2551	3.3820	2.2009	3.3825	2.5919	2.2010	2.1753
C3	1.5602	2.6491		4.0433	2.5021	2.8988	1.1017	4.6866	1.1017	1.1007	4.6872	4.1394
C4	2.6491	1.5602	4.0433		2.8988	2.5021	4.6866	1.1017	4.6872	4.1394	1.1017	1.1007
O5	1.2551	2.4883	2.5021	2.8988		3.6026	2.8566	3.6516	2.8562	3.3474	3.6523	2.3359
O6	2.4883	1.2551	2.8988	2.5021	3.6026		3.6516	2.8566	3.6523	2.3359	2.8562	3.3474
H7	2.2009	3.3820	1.1017	4.6866	2.8566	3.6516		5.1781	1.7867	1.8002	5.4784	4.6837
H8	3.3820	2.2009	4.6866	1.1017	3.6516	2.8566	5.1781		5.4784	4.6837	1.7867	1.8002
H9	2.2010	3.3825	1.1017	4.6872	2.8562	3.6523	1.7867	5.4784		1.8002	5.1796	4.6838
H10	2.1753	2.5919	1.1007	4.1394	3.3474	2.3359	1.8002	4.6837	1.8002		4.6838	4.5105
H11	3.3825	2.2010	4.6872	1.1017	3.6523	2.8562	5.4784	1.7867	5.1796	4.6838		1.8002
H12	2.5919	2.1753	4.1394	1.1007	2.3359	3.3474	4.6837	1.8002	4.6838	4.5105	1.8002

picture of 2,3-Butanedione state 1 conformation 2

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.994	C1	C2	O6	120.918
C1	C3	H7	110.362	C1	C3	H9	110.364
C1	C3	H10	108.435	C2	C1	C3	113.994
C2	C1	O5	120.918	C2	C4	H8	110.362
C2	C4	H11	110.364	C2	C4	H12	108.435
C3	C1	O5	125.088	C4	C2	O6	125.088
H7	C3	H9	108.366	H7	C3	H10	109.651
H8	C4	H11	108.366	H8	C4	H12	109.651
H9	C3	H10	109.654	H11	C4	H12	109.654

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/STO-3G Charges (e)

Number	Element	Mulliken
1	C	0.139
2	C	0.139
3	C	-0.245
4	C	-0.245
5	O	-0.168
6	O	-0.168
7	H	0.090
8	H	0.090
9	H	0.090
10	H	0.095
11	H	0.090
12	H	0.095

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	0.001	0.001
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-35.060	-4.484	0.000
y	-4.484	-33.131	0.000
z	0.000	0.000	-30.962

Traceless
	x	y	z
x	-3.014	-4.484	0.000
y	-4.484	-0.120	0.000
z	0.000	0.000	3.134

Polar
3z²-r²	6.267
x²-y²	-1.929
xy	-4.484
xz	0.000
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	4.710	0.060	0.000
y	0.060	4.537	0.000
z	0.000	0.000	2.287

<r²> (average value of r²) Å²

<r²>	169.454
(<r²>)^1/2	13.017

Conformer 3 (CI)

Jump to S1C1 S1C2

Energy calculated at B3LYP/STO-3G

	hartrees
Energy at 0K	-302.467259
Energy at 298.15K	-302.472713
Nuclear repulsion energy	219.448520

The energy at 298.15K was derived from the energy at 0K and an integrated heat capacity that used the calculated vibrational frequencies.

Vibrational Frequencies calculated at B3LYP/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3482	3107	0.00
2	A_g	3468	3094	0.00
3	A_g	3302	2947	0.00
4	A_g	1803	1609	0.00
5	A_g	1663	1484	0.00
6	A_g	1646	1469	0.00
7	A_g	1512	1349	0.00
8	A_g	1264	1128	0.00
9	A_g	1113	993	0.00
10	A_g	1044	932	0.00
11	A_g	681	608	0.00
12	A_g	613	547	0.00
13	A_g	531	474	0.00
14	A_g	324	290	0.00
15	A_g	84	75	0.00
16	A_u	3482	3107	8.29
17	A_u	3468	3094	0.13
18	A_u	3302	2947	1.48
19	A_u	1811	1616	19.42
20	A_u	1662	1483	10.15
21	A_u	1645	1468	9.42
22	A_u	1510	1348	24.44
23	A_u	1154	1030	120.98
24	A_u	1053	940	7.98
25	A_u	974	869	10.22
26	A_u	520	464	17.07
27	A_u	337	301	1.41
28	A_u	205	183	8.77
29	A_u	116	104	0.91
30	A_u	31	27	3.06

Unscaled Zero Point Vibrational Energy (zpe) 21898.8 cm^-1
Scaled (by 0.8924) Zero Point Vibrational Energy (zpe) 19542.5 cm^-1
See section III.C.1 List or set vibrational scaling factors to change the scale factors used here.
See section III.C.2 Calculate a vibrational scaling factor for a given set of molecules to determine the least squares best scaling factor.

Rotational Constants (cm^-1) from geometry optimized at B3LYP/STO-3G

A	B	C
0.16242	0.10729	0.06624

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

Geometric Data calculated at B3LYP/STO-3G

Point Group is C_i

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	-0.799
C2	0.000	0.000	0.799
C3	1.426	0.000	-1.433
C4	-1.426	0.000	1.433
O5	-1.077	0.000	-1.444
O6	1.077	0.000	1.444
H7	1.565	0.893	-2.063
H8	-1.565	-0.893	2.063
H9	2.168	0.000	-0.620
H10	1.565	-0.893	-2.063
H11	-2.168	-0.000	0.620
H12	-1.565	0.893	2.063

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5986	1.5602	2.6490	1.2550	2.4883	2.2010	3.3822	2.1749	2.2010	2.5911	3.3822
C2	1.5986		2.6490	1.5602	2.4883	1.2550	3.3822	2.2010	2.5911	3.3822	2.1749	2.2010
C3	1.5602	2.6490		4.0432	2.5024	2.8984	1.1017	4.6868	1.1007	1.1017	4.1387	4.6868
C4	2.6490	1.5602	4.0432		2.8984	2.5024	4.6868	1.1017	4.1387	4.6868	1.1007	1.1017
O5	1.2550	2.4883	2.5024	2.8984		3.6025	2.8568	3.6515	3.3472	2.8569	2.3348	3.6515
O6	2.4883	1.2550	2.8984	2.5024	3.6025		3.6515	2.8568	2.3348	3.6515	3.3472	2.8569
H7	2.2010	3.3822	1.1017	4.6868	2.8568	3.6515		5.4783	1.8003	1.7867	4.6831	5.1788
H8	3.3822	2.2010	4.6868	1.1017	3.6515	2.8568	5.4783		4.6831	5.1788	1.8003	1.7867
H9	2.1749	2.5911	1.1007	4.1387	3.3472	2.3348	1.8003	4.6831		1.8003	4.5092	4.6831
H10	2.2010	3.3822	1.1017	4.6868	2.8569	3.6515	1.7867	5.1788	1.8003		4.6831	5.4784
H11	2.5911	2.1749	4.1387	1.1007	2.3348	3.3472	4.6831	1.8003	4.5092	4.6831		1.8003
H12	3.3822	2.2010	4.6868	1.1017	3.6515	2.8569	5.1788	1.7867	4.6831	5.4784	1.8003

picture of 2,3-Butanedione state 1 conformation 3

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C4	113.980	C1	C2	O6	120.909
C1	C3	H7	110.366	C1	C3	H9	108.407
C1	C3	H10	110.369	C2	C1	C3	113.980
C2	C1	O5	120.909	C2	C4	H8	110.366
C2	C4	H11	108.407	C2	C4	H12	110.369
C3	C1	O5	125.111	C4	C2	O6	125.111
H7	C3	H9	109.658	H7	C3	H10	108.371
H8	C4	H11	109.658	H8	C4	H12	108.371
H9	C3	H10	109.662	H11	C4	H12	109.662

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/STO-3G Charges (e)

Number	Element	Mulliken
1	C	0.139
2	C	0.139
3	C	-0.245
4	C	-0.245
5	O	-0.168
6	O	-0.168
7	H	0.090
8	H	0.090
9	H	0.095
10	H	0.090
11	H	0.095
12	H	0.090

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.000	0.000	0.000	0.000
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-33.962	0.000	-4.583
y	0.000	-30.961	0.000
z	-4.583	0.000	-34.229

Traceless
	x	y	z
x	-1.367	0.000	-4.583
y	0.000	3.134	0.000
z	-4.583	0.000	-1.767

Polar
3z²-r²	-3.535
x²-y²	-3.001
xy	0.000
xz	-4.583
yz	0.000

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	4.694	0.000	0.079
y	0.000	2.287	0.000
z	0.079	0.000	4.553

<r²> (average value of r²) Å²

<r²>	169.442
(<r²>)^1/2	13.017

All results from a given calculation for C₄H₆O₂ (2,3-Butanedione)

using model chemistry: B3LYP/STO-3G

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

	Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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All results from a given calculation for C4H6O2 (2,3-Butanedione)

using model chemistry: B3LYP/STO-3G

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

All results from a given calculation for C₄H₆O₂ (2,3-Butanedione)