CCCBDB calculation results Page

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

Conformer 1 (C2H)

Jump to S1C2

Energy calculated at LSDA/6-31G**

	hartrees
Energy at 0K	-304.859203
Energy at 298.15K
Nuclear repulsion energy	227.210994

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 LSDA/6-31G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3135	3076	0.00
2	A_g	2999	2943	0.00
3	A_g	1794	1760	0.00
4	A_g	1384	1358	0.00
5	A_g	1357	1332	0.00
6	A_g	1262	1239	0.00
7	A_g	967	949	0.00
8	A_g	698	685	0.00
9	A_g	518	508	0.00
10	A_g	355	348	0.00
11	A_u	3071	3013	0.15
12	A_u	1383	1357	30.19
13	A_u	890	874	10.12
14	A_u	328	322	2.05
15	A_u	98	96	1.95
16	A_u	34i	34i	10.30
17	B_g	3071	3014	0.00
18	B_g	1390	1364	0.00
19	B_g	1019	1000	0.00
20	B_g	602	590	0.00
21	B_g	48	47	0.00
22	B_u	3136	3077	4.26
23	B_u	2999	2943	3.27
24	B_u	1800	1766	204.07
25	B_u	1384	1358	31.12
26	B_u	1322	1297	141.80
27	B_u	1118	1097	77.41
28	B_u	899	882	7.37
29	B_u	519	509	34.12
30	B_u	234	229	19.04

Unscaled Zero Point Vibrational Energy (zpe) 19871.9 cm^-1
Scaled (by 0.9813) Zero Point Vibrational Energy (zpe) 19500.3 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 LSDA/6-31G**

A	B	C
0.17541	0.11629	0.07176

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

Geometric Data calculated at LSDA/6-31G**

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.076	0.761	0.000
C2	0.076	-0.761	0.000
C3	1.192	1.532	0.000
C4	-1.192	-1.532	0.000
O5	-1.192	1.248	0.000
O6	1.192	-1.248	0.000
H7	0.985	2.610	0.000
H8	-0.985	-2.610	0.000
H9	1.802	1.248	0.875
H10	1.802	1.248	-0.875
H11	-1.802	-1.248	0.875
H12	-1.802	-1.248	-0.875

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5297	1.4841	2.5507	1.2182	2.3761	2.1315	3.4917	2.1284	2.1284	2.7902	2.7902
C2	1.5297		2.5507	1.4841	2.3761	1.2182	3.4917	2.1315	2.7902	2.7902	2.1284	2.1284
C3	1.4841	2.5507		3.8830	2.4014	2.7806	1.0977	4.6796	1.1037	1.1037	4.1792	4.1792
C4	2.5507	1.4841	3.8830		2.7806	2.4014	4.6796	1.0977	4.1792	4.1792	1.1037	1.1037
O5	1.2182	2.3761	2.4014	2.7806		3.4525	2.5678	3.8641	3.1199	3.1199	2.7151	2.7151
O6	2.3761	1.2182	2.7806	2.4014	3.4525		3.8641	2.5678	2.7151	2.7151	3.1199	3.1199
H7	2.1315	3.4917	1.0977	4.6796	2.5678	3.8641		5.5795	1.8134	1.8134	4.8396	4.8396
H8	3.4917	2.1315	4.6796	1.0977	3.8641	2.5678	5.5795		4.8396	4.8396	1.8134	1.8134
H9	2.1284	2.7902	1.1037	4.1792	3.1199	2.7151	1.8134	4.8396		1.7496	4.3851	4.7213
H10	2.1284	2.7902	1.1037	4.1792	3.1199	2.7151	1.8134	4.8396	1.7496		4.7213	4.3851
H11	2.7902	2.1284	4.1792	1.1037	2.7151	3.1199	4.8396	1.8134	4.3851	4.7213		1.7496
H12	2.7902	2.1284	4.1792	1.1037	2.7151	3.1199	4.8396	1.8134	4.7213	4.3851	1.7496

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	115.624	C1	C2	O6	119.258
C1	C3	H7	110.405	C1	C3	H9	109.799
C1	C3	H10	109.799	C2	C1	C3	115.624
C2	C1	O5	119.258	C2	C4	H8	110.405
C2	C4	H11	109.799	C2	C4	H12	109.799
C3	C1	O5	125.117	C4	C2	O6	125.117
H7	C3	H9	110.921	H7	C3	H10	110.921
H8	C4	H11	110.921	H8	C4	H12	110.921
H9	C3	H10	104.860	H11	C4	H12	104.860

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at LSDA/6-31G** Charges (e)

Number	Element	Mulliken
1	C	0.320
2	C	0.320
3	C	-0.498
4	C	-0.498
5	O	-0.366
6	O	-0.366
7	H	0.170
8	H	0.170
9	H	0.187
10	H	0.187
11	H	0.187
12	H	0.187

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	-37.240	7.128	0.000
y	7.128	-36.025	0.000
z	0.000	0.000	-33.187

Traceless
	x	y	z
x	-2.634	7.128	0.000
y	7.128	-0.811	0.000
z	0.000	0.000	3.446

Polar
3z²-r²	6.892
x²-y²	-1.215
xy	7.128
xz	0.000
yz	0.000

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

	x	y	z
x	8.311	0.175	0.000
y	0.175	7.533	0.000
z	0.000	0.000	4.792

<r²> (average value of r²) Å²

<r²>	159.950
(<r²>)^1/2	12.647

Conformer 2 (C2)

Jump to S1C1

Energy calculated at LSDA/6-31G**

	hartrees
Energy at 0K	-304.859244
Energy at 298.15K	-304.865062
Nuclear repulsion energy	227.178987

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 LSDA/6-31G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3135	3077	0.10
2	A	3072	3015	0.10
3	A	2995	2939	0.00
4	A	1792	1759	1.51
5	A	1396	1370	1.55
6	A	1378	1352	26.44
7	A	1350	1325	5.94
8	A	1256	1233	0.00
9	A	967	949	0.01
10	A	892	876	11.51
11	A	695	682	0.14
12	A	521	511	0.14
13	A	361	354	0.40
14	A	323	317	1.83
15	A	99	97	1.15
16	A	49	48	10.26
17	B	3136	3077	1.47
18	B	3072	3015	1.88
19	B	2995	2939	3.01
20	B	1799	1765	200.91
21	B	1394	1368	28.30
22	B	1385	1359	9.69
23	B	1318	1293	144.78
24	B	1114	1093	79.05
25	B	1019	1000	2.02
26	B	906	889	4.16
27	B	600	589	0.37
28	B	516	507	30.78
29	B	245	241	19.19
30	B	82	81	0.91

Unscaled Zero Point Vibrational Energy (zpe) 19930.5 cm^-1
Scaled (by 0.9813) Zero Point Vibrational Energy (zpe) 19557.8 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 LSDA/6-31G**

A	B	C
0.17531	0.11588	0.07186

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

Geometric Data calculated at LSDA/6-31G**

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.076	0.762	-0.015
C2	0.076	-0.762	-0.015
C3	1.190	1.531	0.072
C4	-1.190	-1.531	0.072
O5	-1.190	1.250	-0.087
O6	1.190	-1.250	-0.087
H7	1.018	2.587	-0.177
H8	-1.018	-2.587	-0.177
H9	1.586	1.458	1.101
H10	1.958	1.068	-0.569
H11	-1.586	-1.458	1.101
H12	-1.958	-1.068	-0.569

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5317	1.4838	2.5511	1.2184	2.3784	2.1334	3.4824	2.1199	2.1300	2.9082	2.6831
C2	1.5317		2.5511	1.4838	2.3784	1.2184	3.4824	2.1334	2.9082	2.6831	2.1199	2.1300
C3	1.4838	2.5511		3.8785	2.4018	2.7859	1.0979	4.6790	1.1055	1.1019	4.2076	4.1325
C4	2.5511	1.4838	3.8785		2.7859	2.4018	4.6790	1.0979	4.2076	4.1325	1.1055	1.1019
O5	1.2184	2.3784	2.4018	2.7859		3.4519	2.5824	3.8417	3.0269	3.1898	2.9842	2.4894
O6	2.3784	1.2184	2.7859	2.4018	3.4519		3.8417	2.5824	2.9842	2.4894	3.0269	3.1898
H7	2.1334	3.4824	1.0979	4.6790	2.5824	3.8417		5.5594	1.7970	1.8283	4.9775	4.7295
H8	3.4824	2.1334	4.6790	1.0979	3.8417	2.5824	5.5594		4.9775	4.7295	1.7970	1.8283
H9	2.1199	2.9082	1.1055	4.2076	3.0269	2.9842	1.7970	4.9775		1.7548	4.3092	4.6619
H10	2.1300	2.6831	1.1019	4.1325	3.1898	2.4894	1.8283	4.7295	1.7548		4.6619	4.4610
H11	2.9082	2.1199	4.2076	1.1055	2.9842	3.0269	4.9775	1.7970	4.3092	4.6619		1.7548
H12	2.6831	2.1300	4.1325	1.1019	2.4894	3.1898	4.7295	1.8283	4.6619	4.4610	1.7548

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	115.546	C1	C2	O6	119.290
C1	C3	H7	110.561	C1	C3	H9	109.036
C1	C3	H10	110.047	C2	C1	C3	115.546
C2	C1	O5	119.290	C2	C4	H8	110.561
C2	C4	H11	109.036	C2	C4	H12	110.047
C3	C1	O5	125.165	C4	C2	O6	125.165
H7	C3	H9	109.285	H7	C3	H10	112.431
H8	C4	H11	109.285	H8	C4	H12	112.431
H9	C3	H10	105.305	H11	C4	H12	105.305

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at LSDA/6-31G** Charges (e)

Number	Element	Mulliken
1	C	0.321
2	C	0.321
3	C	-0.500
4	C	-0.500
5	O	-0.368
6	O	-0.368
7	H	0.172
8	H	0.172
9	H	0.187
10	H	0.187
11	H	0.187
12	H	0.187

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	0.496	0.496
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-37.394	7.102	0.000
y	7.102	-35.853	0.000
z	0.000	0.000	-33.188

Traceless
	x	y	z
x	-2.874	7.102	0.000
y	7.102	-0.562	0.000
z	0.000	0.000	3.436

Polar
3z²-r²	6.871
x²-y²	-1.542
xy	7.102
xz	0.000
yz	0.000

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

	x	y	z
x	8.240	0.251	0.000
y	0.251	7.613	0.000
z	0.000	0.000	4.839

<r²> (average value of r²) Å²

<r²>	159.998
(<r²>)^1/2	12.649

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

using model chemistry: LSDA/6-31G**

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

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

using model chemistry: LSDA/6-31G**

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

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