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/6-31+G**

	hartrees
Energy at 0K	-305.662206
Energy at 298.15K	-305.668361
HF Energy	-304.704762
Nuclear repulsion energy	226.283121

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/6-31+G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3266	3043	0.00
2	A_g	3146	2930	0.00
3	A_g	1867	1739	0.00
4	A_g	1519	1415	0.00
5	A_g	1462	1362	0.00
6	A_g	1353	1261	0.00
7	A_g	1056	983	0.00
8	A_g	724	675	0.00
9	A_g	547	510	0.00
10	A_g	372	346	0.00
11	A_u	3226	3005	6.88
12	A_u	1515	1412	19.32
13	A_u	999	931	1.93
14	A_u	361	336	7.67
15	A_u	120	112	0.13
16	A_u	46	43	11.57
17	B_g	3226	3005	0.00
18	B_g	1519	1415	0.00
19	B_g	1094	1019	0.00
20	B_g	625	582	0.00
21	B_g	118	110	0.00
22	B_u	3267	3043	11.17
23	B_u	3145	2930	2.05
24	B_u	1861	1734	205.61
25	B_u	1519	1415	26.49
26	B_u	1450	1351	49.90
27	B_u	1178	1097	70.98
28	B_u	958	893	14.50
29	B_u	558	520	44.35
30	B_u	243	227	16.44

Unscaled Zero Point Vibrational Energy (zpe) 21168.7 cm^-1
Scaled (by 0.9316) Zero Point Vibrational Energy (zpe) 19720.7 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/6-31+G**

A	B	C
0.17744	0.11253	0.07063

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

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

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.051	0.745	0.000
C2	0.051	-0.745	0.000
C3	1.180	1.591	0.000
C4	-1.180	-1.591	0.000
O5	-1.180	1.228	0.000
O6	1.180	-1.228	0.000
H7	0.892	2.635	0.000
H8	-0.892	-2.635	0.000
H9	1.786	1.372	0.877
H10	1.786	1.372	-0.877
H11	-1.786	-1.372	0.877
H12	-1.786	-1.372	-0.877

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.4938	1.4933	2.5942	1.2274	2.3252	2.1125	3.4836	2.1295	2.1295	2.8739	2.8739
C2	1.4938		2.5942	1.4933	2.3252	1.2274	3.4836	2.1125	2.8739	2.8739	2.1295	2.1295
C3	1.4933	2.5942		3.9609	2.3871	2.8184	1.0836	4.7067	1.0878	1.0878	4.2825	4.2825
C4	2.5942	1.4933	3.9609		2.8184	2.3871	4.7067	1.0836	4.2825	4.2825	1.0878	1.0878
O5	1.2274	2.3252	2.3871	2.8184		3.4051	2.5048	3.8738	3.0954	3.0954	2.8097	2.8097
O6	2.3252	1.2274	2.8184	2.3871	3.4051		3.8738	2.5048	2.8097	2.8097	3.0954	3.0954
H7	2.1125	3.4836	1.0836	4.7067	2.5048	3.8738		5.5646	1.7785	1.7785	4.8988	4.8988
H8	3.4836	2.1125	4.7067	1.0836	3.8738	2.5048	5.5646		4.8988	4.8988	1.7785	1.7785
H9	2.1295	2.8739	1.0878	4.2825	3.0954	2.8097	1.7785	4.8988		1.7533	4.5036	4.8329
H10	2.1295	2.8739	1.0878	4.2825	3.0954	2.8097	1.7785	4.8988	1.7533		4.8329	4.5036
H11	2.8739	2.1295	4.2825	1.0878	2.8097	3.0954	4.8988	1.7785	4.5036	4.8329		1.7533
H12	2.8739	2.1295	4.2825	1.0878	2.8097	3.0954	4.8988	1.7785	4.8329	4.5036	1.7533

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	120.565	C1	C2	O6	117.075
C1	C3	H7	109.096	C1	C3	H9	110.193
C1	C3	H10	110.193	C2	C1	C3	120.565
C2	C1	O5	117.075	C2	C4	H8	109.096
C2	C4	H11	110.193	C2	C4	H12	110.193
C3	C1	O5	122.359	C4	C2	O6	122.359
H7	C3	H9	109.978	H7	C3	H10	109.978
H8	C4	H11	109.978	H8	C4	H12	109.978
H9	C3	H10	107.389	H11	C4	H12	107.389

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (C2)

Jump to S1C1 S1C3

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

	hartrees
Energy at 0K	-305.662206
Energy at 298.15K	-305.668362
HF Energy	-304.704734
Nuclear repulsion energy	226.289737

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/6-31+G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3267	3043	0.00
2	A	3225	3005	6.86
3	A	3145	2930	0.00
4	A	1866	1738	0.00
5	A	1519	1415	0.00
6	A	1515	1411	19.35
7	A	1463	1363	0.00
8	A	1353	1261	0.00
9	A	1056	983	0.00
10	A	999	931	1.94
11	A	724	675	0.00
12	A	547	510	0.00
13	A	372	346	0.00
14	A	361	336	7.69
15	A	120	111	0.13
16	A	46	43	11.55
17	B	3267	3044	11.20
18	B	3225	3005	0.00
19	B	3145	2930	2.01
20	B	1860	1733	205.60
21	B	1519	1415	26.56
22	B	1518	1415	0.00
23	B	1451	1351	50.05
24	B	1178	1098	71.06
25	B	1094	1019	0.00
26	B	959	893	14.28
27	B	626	583	0.00
28	B	558	520	44.40
29	B	243	227	16.41
30	B	118	110	0.00

Unscaled Zero Point Vibrational Energy (zpe) 21169.0 cm^-1
Scaled (by 0.9316) Zero Point Vibrational Energy (zpe) 19721.1 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 MP3=FULL/6-31+G**

A	B	C
0.17742	0.11256	0.07064

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

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

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.080	0.768	0.000
C2	-0.080	-0.768	0.000
C3	-1.192	1.576	0.000
C4	1.192	-1.576	0.000
O5	1.192	1.251	-0.000
O6	-1.192	-1.251	-0.000
H7	-0.940	2.631	-0.000
H8	0.940	-2.631	-0.000
H9	-1.791	1.328	-0.874
H10	-1.791	1.329	0.875
H11	1.791	-1.328	-0.874
H12	1.791	-1.329	0.875

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5452	1.5063	2.5947	1.2125	2.3865	2.1233	3.5065	2.1392	2.1392	2.8440	2.8442
C2	1.5452		2.5947	1.5063	2.3865	1.2125	3.5065	2.1233	2.8440	2.8442	2.1392	2.1392
C3	1.5063	2.5947		3.9516	2.4061	2.8267	1.0846	4.7161	1.0881	1.0881	4.2538	4.2538
C4	2.5947	1.5063	3.9516		2.8267	2.4061	4.7161	1.0846	4.2538	4.2538	1.0881	1.0881
O5	1.2125	2.3865	2.4061	2.8267		3.4560	2.5399	3.8899	3.1092	3.1093	2.7882	2.7888
O6	2.3865	1.2125	2.8267	2.4061	3.4560		3.8899	2.5399	2.7882	2.7888	3.1092	3.1093
H7	2.1233	3.5065	1.0846	4.7161	2.5399	3.8899		5.5876	1.7843	1.7843	4.8885	4.8887
H8	3.5065	2.1233	4.7161	1.0846	3.8899	2.5399	5.5876		4.8885	4.8887	1.7843	1.7843
H9	2.1392	2.8440	1.0881	4.2538	3.1092	2.7882	1.7843	4.8885		1.7485	4.4594	4.7899
H10	2.1392	2.8442	1.0881	4.2538	3.1093	2.7888	1.7843	4.8887	1.7485		4.7899	4.4592
H11	2.8440	2.1392	4.2538	1.0881	2.7882	3.1092	4.8885	1.7843	4.4594	4.7899		1.7485
H12	2.8442	2.1392	4.2538	1.0881	2.7888	3.1093	4.8887	1.7843	4.7899	4.4592	1.7485

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	116.487	C1	C2	O6	119.366
C1	C3	H7	108.989	C1	C3	H9	110.043
C1	C3	H10	110.044	C2	C1	C3	116.487
C2	C1	O5	119.366	C2	C4	H8	108.989
C2	C4	H11	110.043	C2	C4	H12	110.044
C3	C1	O5	124.147	C4	C2	O6	124.147
H7	C3	H9	110.411	H7	C3	H10	110.413
H8	C4	H11	110.411	H8	C4	H12	110.413
H9	C3	H10	106.928	H11	C4	H12	106.928

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

Conformer 3 (CI)

Jump to S1C1 S1C2

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

	hartrees
Energy at 0K	-305.662206
Energy at 298.15K	-305.668357
HF Energy	-304.704749
Nuclear repulsion energy	226.296911

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/6-31+G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3267	3043	0.00
2	A_g	3226	3005	0.00
3	A_g	3146	2931	0.00
4	A_g	1866	1739	0.00
5	A_g	1519	1415	0.00
6	A_g	1518	1415	0.00
7	A_g	1463	1363	0.00
8	A_g	1353	1261	0.00
9	A_g	1094	1019	0.00
10	A_g	1056	983	0.00
11	A_g	724	675	0.00
12	A_g	625	583	0.00
13	A_g	547	510	0.00
14	A_g	372	346	0.00
15	A_g	117	109	0.00
16	A_u	3267	3044	11.20
17	A_u	3225	3005	6.86
18	A_u	3146	2931	2.01
19	A_u	1860	1733	205.72
20	A_u	1519	1415	26.54
21	A_u	1515	1411	19.35
22	A_u	1451	1351	50.10
23	A_u	1178	1098	71.08
24	A_u	999	931	1.94
25	A_u	959	893	14.26
26	A_u	558	520	44.40
27	A_u	361	336	7.69
28	A_u	243	227	16.42
29	A_u	119	111	0.14
30	A_u	46	42	11.54

Unscaled Zero Point Vibrational Energy (zpe) 21168.5 cm^-1
Scaled (by 0.9316) Zero Point Vibrational Energy (zpe) 19720.5 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 MP3=FULL/6-31+G**

A	B	C
0.17744	0.11256	0.07065

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

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

Point Group is C_i

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.003	-0.000	-0.773
C2	0.003	0.000	0.773
C3	1.342	-0.000	-1.450
C4	-1.342	0.000	1.450
O5	-1.062	-0.000	-1.363
O6	1.062	0.000	1.363
H7	1.913	0.875	-1.146
H8	-1.913	-0.875	1.146
H9	1.914	-0.873	-1.143
H10	1.196	-0.001	-2.525
H11	-1.914	0.873	1.143
H12	-1.196	0.001	2.525

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5452	1.5063	2.5948	1.2125	2.3866	2.1392	2.8447	2.1393	2.1233	2.8437	3.5065
C2	1.5452		2.5948	1.5063	2.3866	1.2125	2.8447	2.1392	2.8437	3.5065	2.1393	2.1233
C3	1.5063	2.5948		3.9517	2.4061	2.8268	1.0881	4.2542	1.0881	1.0847	4.2536	4.7161
C4	2.5948	1.5063	3.9517		2.8268	2.4061	4.2542	1.0881	4.2536	4.7161	1.0881	1.0847
O5	1.2125	2.3866	2.4061	2.8268		3.4560	3.1087	2.7897	3.1098	2.5399	2.7875	3.8900
O6	2.3866	1.2125	2.8268	2.4061	3.4560		2.7897	3.1087	2.7875	3.8900	3.1098	2.5399
H7	2.1392	2.8447	1.0881	4.2542	3.1087	2.7897		4.7905	1.7485	1.7842	4.4594	4.8889
H8	2.8447	2.1392	4.2542	1.0881	2.7897	3.1087	4.7905		4.4594	4.8889	1.7485	1.7842
H9	2.1393	2.8437	1.0881	4.2536	3.1098	2.7875	1.7485	4.4594		1.7843	4.7894	4.8884
H10	2.1233	3.5065	1.0847	4.7161	2.5399	3.8900	1.7842	4.8889	1.7843		4.8884	5.5876
H11	2.8437	2.1393	4.2536	1.0881	2.7875	3.1098	4.4594	1.7485	4.7894	4.8884		1.7843
H12	3.5065	2.1233	4.7161	1.0847	3.8900	2.5399	4.8889	1.7842	4.8884	5.5876	1.7843

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	116.489	C1	C2	O6	119.368
C1	C3	H7	110.038	C1	C3	H9	110.050
C1	C3	H10	108.988	C2	C1	C3	116.489
C2	C1	O5	119.368	C2	C4	H8	110.038
C2	C4	H11	110.050	C2	C4	H12	108.988
C3	C1	O5	124.143	C4	C2	O6	124.143
H7	C3	H9	106.930	H7	C3	H10	110.405
H8	C4	H11	106.930	H8	C4	H12	110.405
H9	C3	H10	110.417	H11	C4	H12	110.417

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

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

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/6-31+G**

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

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