CCCBDB calculation results Page

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

Conformer 1 (C2H)

Jump to S1C2 S1C3

Energy calculated at MP3=FULL/6-31G*

	hartrees
Energy at 0K	-305.593788
Energy at 298.15K	-305.600012
HF Energy	-304.686927
Nuclear repulsion energy	226.294925

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 MP3=FULL/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3233	3033	0.00
2	A_g	3120	2928	0.00
3	A_g	1885	1769	0.00
4	A_g	1524	1430	0.00
5	A_g	1466	1376	0.00
6	A_g	1363	1279	0.00
7	A_g	1056	991	0.00
8	A_g	725	681	0.00
9	A_g	552	518	0.00
10	A_g	375	352	0.00
11	A_u	3194	2997	4.97
12	A_u	1522	1428	20.95
13	A_u	1008	946	4.81
14	A_u	361	339	6.37
15	A_u	130	122	0.01
16	A_u	63	59	10.04
17	B_g	3194	2997	0.00
18	B_g	1525	1431	0.00
19	B_g	1105	1037	0.00
20	B_g	636	597	0.00
21	B_g	131	123	0.00
22	B_u	3233	3034	9.71
23	B_u	3120	2928	0.64
24	B_u	1879	1763	163.50
25	B_u	1524	1430	26.89
26	B_u	1453	1364	61.25
27	B_u	1181	1109	79.26
28	B_u	961	902	11.49
29	B_u	558	523	44.93
30	B_u	247	232	16.83

Unscaled Zero Point Vibrational Energy (zpe) 21161.6 cm^-1
Scaled (by 0.9383) Zero Point Vibrational Energy (zpe) 19855.9 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 MP3=FULL/6-31G*

A	B	C
0.17699	0.11297	0.07075

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

Geometric Data calculated at MP3=FULL/6-31G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.053	0.743	0.000
C2	0.053	-0.743	0.000
C3	1.180	1.587	0.000
C4	-1.180	-1.587	0.000
O5	-1.180	1.224	0.000
O6	1.180	-1.224	0.000
H7	0.893	2.637	0.000
H8	-0.893	-2.637	0.000
H9	1.790	1.367	0.881
H10	1.790	1.367	-0.881
H11	-1.790	-1.367	0.881
H12	-1.790	-1.367	-0.881

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.4907	1.4939	2.5884	1.2256	2.3221	2.1165	3.4832	2.1356	2.1356	2.8719	2.8719
C2	1.4907		2.5884	1.4939	2.3221	1.2256	3.4832	2.1165	2.8719	2.8719	2.1356	2.1356
C3	1.4939	2.5884		3.9549	2.3884	2.8106	1.0890	4.7048	1.0933	1.0933	4.2806	4.2806
C4	2.5884	1.4939	3.9549		2.8106	2.3884	4.7048	1.0890	4.2806	4.2806	1.0933	1.0933
O5	1.2256	2.3221	2.3884	2.8106		3.4009	2.5089	3.8716	3.1015	3.1015	2.8039	2.8039
O6	2.3221	1.2256	2.8106	2.3884	3.4009		3.8716	2.5089	2.8039	2.8039	3.1015	3.1015
H7	2.1165	3.4832	1.0890	4.7048	2.5089	3.8716		5.5679	1.7867	1.7867	4.8996	4.8996
H8	3.4832	2.1165	4.7048	1.0890	3.8716	2.5089	5.5679		4.8996	4.8996	1.7867	1.7867
H9	2.1356	2.8719	1.0933	4.2806	3.1015	2.8039	1.7867	4.8996		1.7611	4.5049	4.8369
H10	2.1356	2.8719	1.0933	4.2806	3.1015	2.8039	1.7867	4.8996	1.7611		4.8369	4.5049
H11	2.8719	2.1356	4.2806	1.0933	2.8039	3.1015	4.8996	1.7867	4.5049	4.8369		1.7611
H12	2.8719	2.1356	4.2806	1.0933	2.8039	3.1015	4.8996	1.7867	4.8369	4.5049	1.7611

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	120.284	C1	C2	O6	117.158
C1	C3	H7	109.050	C1	C3	H9	110.316
C1	C3	H10	110.316	C2	C1	C3	120.284
C2	C1	O5	117.158	C2	C4	H8	109.050
C2	C4	H11	110.316	C2	C4	H12	110.316
C3	C1	O5	122.558	C4	C2	O6	122.558
H7	C3	H9	109.922	H7	C3	H10	109.922
H8	C4	H11	109.922	H8	C4	H12	109.922
H9	C3	H10	107.303	H11	C4	H12	107.303

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (C2)

Jump to S1C1 S1C3

Energy calculated at MP3=FULL/6-31G*

	hartrees
Energy at 0K	-305.593788
Energy at 298.15K	-305.600013
HF Energy	-304.686893
Nuclear repulsion energy	226.299154

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 MP3=FULL/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3233	3034	0.00
2	A	3193	2996	4.95
3	A	3120	2928	0.00
4	A	1884	1768	0.00
5	A	1524	1430	0.00
6	A	1522	1428	20.98
7	A	1467	1376	0.00
8	A	1363	1279	0.00
9	A	1056	991	0.00
10	A	1008	946	4.82
11	A	726	681	0.00
12	A	552	518	0.00
13	A	375	352	0.00
14	A	362	339	6.39
15	A	130	122	0.01
16	A	64	60	10.02
17	B	3233	3034	9.73
18	B	3193	2996	0.00
19	B	3120	2928	0.62
20	B	1877	1762	163.39
21	B	1525	1431	0.00
22	B	1524	1430	26.97
23	B	1454	1364	61.41
24	B	1182	1109	79.30
25	B	1106	1037	0.00
26	B	961	902	11.30
27	B	636	597	0.00
28	B	558	523	44.98
29	B	247	232	16.79
30	B	130	122	0.00

Unscaled Zero Point Vibrational Energy (zpe) 21161.9 cm^-1
Scaled (by 0.9383) Zero Point Vibrational Energy (zpe) 19856.2 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 MP3=FULL/6-31G*

A	B	C
0.17697	0.11299	0.07076

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

Geometric Data calculated at MP3=FULL/6-31G*

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.081	0.767	0.000
C2	-0.081	-0.767	0.000
C3	-1.193	1.571	0.000
C4	1.193	-1.571	0.000
O5	1.193	1.249	-0.000
O6	-1.193	-1.249	-0.000
H7	-0.944	2.632	-0.000
H8	0.944	-2.632	-0.000
H9	-1.796	1.322	-0.878
H10	-1.796	1.322	0.879
H11	1.796	-1.322	-0.878
H12	1.796	-1.322	0.879

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5418	1.5068	2.5885	1.2120	2.3843	2.1286	3.5067	2.1454	2.1454	2.8414	2.8416
C2	1.5418		2.5885	1.5068	2.3843	1.2120	3.5067	2.1286	2.8414	2.8416	2.1454	2.1454
C3	1.5068	2.5885		3.9451	2.4081	2.8193	1.0905	4.7151	1.0939	1.0939	4.2512	4.2514
C4	2.5885	1.5068	3.9451		2.8193	2.4081	4.7151	1.0905	4.2512	4.2514	1.0939	1.0939
O5	1.2120	2.3843	2.4081	2.8193		3.4540	2.5458	3.8889	3.1161	3.1162	2.7823	2.7828
O6	2.3843	1.2120	2.8193	2.4081	3.4540		3.8889	2.5458	2.7823	2.7828	3.1161	3.1162
H7	2.1286	3.5067	1.0905	4.7151	2.5458	3.8889		5.5927	1.7929	1.7930	4.8899	4.8902
H8	3.5067	2.1286	4.7151	1.0905	3.8889	2.5458	5.5927		4.8899	4.8902	1.7929	1.7930
H9	2.1454	2.8414	1.0939	4.2512	3.1161	2.7823	1.7929	4.8899		1.7572	4.4596	4.7934
H10	2.1454	2.8416	1.0939	4.2514	3.1162	2.7828	1.7930	4.8902	1.7572		4.7934	4.4597
H11	2.8414	2.1454	4.2512	1.0939	2.7823	3.1161	4.8899	1.7929	4.4596	4.7934		1.7572
H12	2.8416	2.1454	4.2514	1.0939	2.7828	3.1162	4.8902	1.7930	4.7934	4.4597	1.7572

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	116.210	C1	C2	O6	119.470
C1	C3	H7	109.021	C1	C3	H9	110.145
C1	C3	H10	110.146	C2	C1	C3	116.210
C2	C1	O5	119.470	C2	C4	H8	109.021
C2	C4	H11	110.145	C2	C4	H12	110.146
C3	C1	O5	124.321	C4	C2	O6	124.321
H7	C3	H9	110.324	H7	C3	H10	110.325
H8	C4	H11	110.324	H8	C4	H12	110.325
H9	C3	H10	106.866	H11	C4	H12	106.866

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

Conformer 3 (CI)

Jump to S1C1 S1C2

Energy calculated at MP3=FULL/6-31G*

	hartrees
Energy at 0K	-305.593788
Energy at 298.15K	-305.600008
HF Energy	-304.686903
Nuclear repulsion energy	226.303833

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 MP3=FULL/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3233	3034	0.00
2	A_g	3194	2997	0.00
3	A_g	3120	2928	0.00
4	A_g	1884	1768	0.00
5	A_g	1525	1431	0.00
6	A_g	1524	1430	0.00
7	A_g	1467	1376	0.00
8	A_g	1363	1279	0.00
9	A_g	1105	1037	0.00
10	A_g	1056	991	0.00
11	A_g	726	681	0.00
12	A_g	636	597	0.00
13	A_g	552	518	0.00
14	A_g	375	352	0.00
15	A_g	129	121	0.00
16	A_u	3234	3034	9.72
17	A_u	3194	2997	4.95
18	A_u	3120	2928	0.61
19	A_u	1878	1762	163.45
20	A_u	1524	1430	26.98
21	A_u	1522	1428	20.98
22	A_u	1454	1364	61.43
23	A_u	1182	1109	79.33
24	A_u	1008	946	4.82
25	A_u	961	902	11.28
26	A_u	558	523	44.98
27	A_u	362	339	6.38
28	A_u	247	232	16.79
29	A_u	129	121	0.02
30	A_u	63	59	10.02

Unscaled Zero Point Vibrational Energy (zpe) 21161.4 cm^-1
Scaled (by 0.9383) Zero Point Vibrational Energy (zpe) 19855.7 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 MP3=FULL/6-31G*

A	B	C
0.17698	0.11300	0.07076

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

Geometric Data calculated at MP3=FULL/6-31G*

Point Group is C_i

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.006	-0.000	-0.771
C2	0.006	0.000	0.771
C3	1.340	-0.000	-1.447
C4	-1.340	0.000	1.447
O5	-1.066	-0.000	-1.359
O6	1.066	0.000	1.359
H7	1.915	0.880	-1.142
H8	-1.915	-0.880	1.142
H9	1.917	-0.878	-1.140
H10	1.195	-0.001	-2.528
H11	-1.917	0.878	1.140
H12	-1.195	0.001	2.528

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5418	1.5069	2.5885	1.2120	2.3843	2.1453	2.8420	2.1455	2.1286	2.8411	3.5067
C2	1.5418		2.5885	1.5069	2.3843	1.2120	2.8420	2.1453	2.8411	3.5067	2.1455	2.1286
C3	1.5069	2.5885		3.9452	2.4081	2.8193	1.0939	4.2517	1.0939	1.0905	4.2511	4.7151
C4	2.5885	1.5069	3.9452		2.8193	2.4081	4.2517	1.0939	4.2511	4.7151	1.0939	1.0905
O5	1.2120	2.3843	2.4081	2.8193		3.4540	3.1156	2.7838	3.1167	2.5457	2.7816	3.8889
O6	2.3843	1.2120	2.8193	2.4081	3.4540		2.7838	3.1156	2.7816	3.8889	3.1167	2.5457
H7	2.1453	2.8420	1.0939	4.2517	3.1156	2.7838		4.7940	1.7572	1.7929	4.4597	4.8904
H8	2.8420	2.1453	4.2517	1.0939	2.7838	3.1156	4.7940		4.4597	4.8904	1.7572	1.7929
H9	2.1455	2.8411	1.0939	4.2511	3.1167	2.7816	1.7572	4.4597		1.7930	4.7929	4.8899
H10	2.1286	3.5067	1.0905	4.7151	2.5457	3.8889	1.7929	4.8904	1.7930		4.8899	5.5927
H11	2.8411	2.1455	4.2511	1.0939	2.7816	3.1167	4.4597	1.7572	4.7929	4.8899		1.7930
H12	3.5067	2.1286	4.7151	1.0905	3.8889	2.5457	4.8904	1.7929	4.8899	5.5927	1.7930

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	116.212	C1	C2	O6	119.471
C1	C3	H7	110.140	C1	C3	H9	110.152
C1	C3	H10	109.019	C2	C1	C3	116.212
C2	C1	O5	119.471	C2	C4	H8	110.140
C2	C4	H11	110.152	C2	C4	H12	109.019
C3	C1	O5	124.317	C4	C2	O6	124.317
H7	C3	H9	106.868	H7	C3	H10	110.318
H8	C4	H11	106.868	H8	C4	H12	110.318
H9	C3	H10	110.329	H11	C4	H12	110.329

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP3=FULL/6-31G*

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: MP3=FULL/6-31G*

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

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