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 BLYP/STO-3G

	hartrees
Energy at 0K	-302.339165
Energy at 298.15K
Nuclear repulsion energy	216.355987

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 BLYP/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3384	3131	0.00
2	A_g	3200	2961	0.00
3	A_g	1712	1584	0.00
4	A_g	1605	1485	0.00
5	A_g	1473	1363	0.00
6	A_g	1195	1105	0.00
7	A_g	1001	926	0.00
8	A_g	628	581	0.00
9	A_g	479	444	0.00
10	A_g	311	287	0.00
11	A_u	3355	3104	0.07
12	A_u	1606	1486	9.97
13	A_u	1002	927	6.75
14	A_u	305	282	0.21
15	A_u	75	69	1.02
16	A_u	26i	24i	1.92
17	B_g	3355	3104	0.00
18	B_g	1608	1488	0.00
19	B_g	1059	980	0.00
20	B_g	572	529	0.00
21	B_g	32	30	0.00
22	B_u	3385	3131	1.36
23	B_u	3200	2961	2.65
24	B_u	1718	1590	20.89
25	B_u	1607	1487	15.74
26	B_u	1471	1361	11.41
27	B_u	1112	1029	88.26
28	B_u	897	830	38.18
29	B_u	492	455	16.46
30	B_u	184	170	4.45

Unscaled Zero Point Vibrational Energy (zpe) 20999.2 cm^-1
Scaled (by 0.9252) Zero Point Vibrational Energy (zpe) 19428.5 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 BLYP/STO-3G

A	B	C
0.15889	0.10366	0.06429

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

Geometric Data calculated at BLYP/STO-3G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.101	0.806	0.000
C2	0.101	-0.806	0.000
C3	1.254	1.620	0.000
C4	-1.254	-1.620	0.000
O5	-1.254	1.336	0.000
O6	1.254	-1.336	0.000
H7	1.049	2.709	0.000
H8	-1.049	-2.709	0.000
H9	1.852	1.355	0.897
H10	1.852	1.355	-0.897
H11	-1.852	-1.355	0.897
H12	-1.852	-1.355	-0.897

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.6254	1.5807	2.6866	1.2688	2.5349	2.2232	3.6409	2.2178	2.2178	2.9224	2.9224
C2	1.6254		2.6866	1.5807	2.5349	1.2688	3.6409	2.2232	2.9224	2.9224	2.2178	2.2178
C3	1.5807	2.6866		4.0977	2.5243	2.9561	1.1077	4.9037	1.1102	1.1102	4.3934	4.3934
C4	2.6866	1.5807	4.0977		2.9561	2.5243	4.9037	1.1077	4.3934	4.3934	1.1102	1.1102
O5	1.2688	2.5349	2.5243	2.9561		3.6646	2.6815	4.0499	3.2328	3.2328	2.8987	2.8987
O6	2.5349	1.2688	2.9561	2.5243	3.6646		4.0499	2.6815	2.8987	2.8987	3.2328	3.2328
H7	2.2232	3.6409	1.1077	4.9037	2.6815	4.0499		5.8100	1.8117	1.8117	5.0729	5.0729
H8	3.6409	2.2232	4.9037	1.1077	4.0499	2.6815	5.8100		5.0729	5.0729	1.8117	1.8117
H9	2.2178	2.9224	1.1102	4.3934	3.2328	2.8987	1.8117	5.0729		1.7945	4.5887	4.9271
H10	2.2178	2.9224	1.1102	4.3934	3.2328	2.8987	1.8117	5.0729	1.7945		4.9271	4.5887
H11	2.9224	2.2178	4.3934	1.1102	2.8987	3.2328	5.0729	1.8117	4.5887	4.9271		1.7945
H12	2.9224	2.2178	4.3934	1.1102	2.8987	3.2328	5.0729	1.8117	4.9271	4.5887	1.7945

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	113.842	C1	C2	O6	121.808
C1	C3	H7	110.330	C1	C3	H9	109.775
C1	C3	H10	109.775	C2	C1	C3	113.842
C2	C1	O5	121.808	C2	C4	H8	110.330
C2	C4	H11	109.775	C2	C4	H12	109.775
C3	C1	O5	124.351	C4	C2	O6	124.351
H7	C3	H9	109.536	H7	C3	H10	109.536
H8	C4	H11	109.536	H8	C4	H12	109.536
H9	C3	H10	107.847	H11	C4	H12	107.847

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.125
2	C	0.125
3	C	-0.233
4	C	-0.233
5	O	-0.152
6	O	-0.152
7	H	0.084
8	H	0.084
9	H	0.088
10	H	0.088
11	H	0.088
12	H	0.088

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	-34.503	4.283	0.000
y	4.283	-33.287	0.000
z	0.000	0.000	-31.045

Traceless
	x	y	z
x	-2.337	4.283	0.000
y	4.283	-0.512	0.000
z	0.000	0.000	2.850

Polar
3z²-r²	5.700
x²-y²	-1.217
xy	4.283
xz	0.000
yz	0.000

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

	x	y	z
x	5.049	-0.115	0.000
y	-0.115	4.800	0.000
z	0.000	0.000	2.328

<r²> (average value of r²) Å²

<r²>	173.749
(<r²>)^1/2	13.181

Conformer 2 (C2)

Jump to S1C1

Energy calculated at BLYP/STO-3G

	hartrees
Energy at 0K	-302.339609
Energy at 298.15K	-302.344844
Nuclear repulsion energy	216.824889

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 BLYP/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3368	3116	0.00
2	A	3359	3108	0.12
3	A	3196	2957	0.00
4	A	1702	1574	0.00
5	A	1618	1497	9.04
6	A	1602	1482	0.00
7	A	1455	1347	0.00
8	A	1185	1097	0.00
9	A	1007	932	6.94
10	A	988	914	0.00
11	A	631	584	0.00
12	A	499	462	0.00
13	A	309	286	0.71
14	A	302	280	0.00
15	A	117	108	0.53
16	A	40	37	2.92
17	B	3368	3116	9.23
18	B	3359	3108	0.00
19	B	3196	2957	0.53
20	B	1717	1589	18.01
21	B	1619	1498	0.00
22	B	1600	1481	9.14
23	B	1453	1344	23.50
24	B	1105	1022	125.83
25	B	1063	984	0.00
26	B	916	848	20.42
27	B	579	536	0.00
28	B	498	461	12.82
29	B	188	174	8.42
30	B	89	83	0.00

Unscaled Zero Point Vibrational Energy (zpe) 21064.7 cm^-1
Scaled (by 0.9252) Zero Point Vibrational Energy (zpe) 19489.0 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 BLYP/STO-3G

A	B	C
0.15804	0.10480	0.06459

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

Geometric Data calculated at BLYP/STO-3G

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.100	0.808	-0.000
C2	-0.100	-0.808	-0.000
C3	-1.259	1.609	0.000
C4	1.259	-1.609	0.000
O5	1.259	1.326	-0.000
O6	-1.259	-1.326	-0.000
H7	-1.327	2.254	0.900
H8	1.327	-2.254	0.900
H9	-1.327	2.255	-0.900
H10	-2.093	0.877	-0.000
H11	1.327	-2.255	-0.900
H12	2.093	-0.877	-0.000

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.6275	1.5780	2.6797	1.2696	2.5299	2.2228	3.4189	2.2228	2.1943	3.4191	2.6093
C2	1.6275		2.6797	1.5780	2.5299	1.2696	3.4189	2.2228	3.4191	2.6093	2.2228	2.1943
C3	1.5780	2.6797		4.0857	2.5342	2.9347	1.1097	4.7350	1.1097	1.1091	4.7353	4.1732
C4	2.6797	1.5780	4.0857		2.9347	2.5342	4.7350	1.1097	4.7353	4.1732	1.1097	1.1091
O5	1.2696	2.5299	2.5342	2.9347		3.6573	2.8916	3.6922	2.8914	3.3820	3.6925	2.3557
O6	2.5299	1.2696	2.9347	2.5342	3.6573		3.6922	2.8916	3.6925	2.3557	2.8914	3.3820
H7	2.2228	3.4189	1.1097	4.7350	2.8916	3.6922		5.2315	1.8000	1.8146	5.5329	4.7235
H8	3.4189	2.2228	4.7350	1.1097	3.6922	2.8916	5.2315		5.5329	4.7235	1.8000	1.8146
H9	2.2228	3.4191	1.1097	4.7353	2.8914	3.6925	1.8000	5.5329		1.8146	5.2322	4.7237
H10	2.1943	2.6093	1.1091	4.1732	3.3820	2.3557	1.8146	4.7235	1.8146		4.7237	4.5385
H11	3.4191	2.2228	4.7353	1.1097	3.6925	2.8914	5.5329	1.8000	5.2322	4.7237		1.8146
H12	2.6093	2.1943	4.1732	1.1091	2.3557	3.3820	4.7235	1.8146	4.7237	4.5385	1.8146

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	113.424	C1	C2	O6	121.192
C1	C3	H7	110.370	C1	C3	H9	110.373
C1	C3	H10	108.227	C2	C1	C3	113.424
C2	C1	O5	121.192	C2	C4	H8	110.370
C2	C4	H11	110.373	C2	C4	H12	108.227
C3	C1	O5	125.383	C4	C2	O6	125.383
H7	C3	H9	108.391	H7	C3	H10	109.735
H8	C4	H11	108.391	H8	C4	H12	109.735
H9	C3	H10	109.739	H11	C4	H12	109.739

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.125
2	C	0.125
3	C	-0.237
4	C	-0.237
5	O	-0.152
6	O	-0.152
7	H	0.086
8	H	0.086
9	H	0.086
10	H	0.090
11	H	0.086
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	-34.805	-4.239	0.000
y	-4.239	-32.951	0.000
z	0.000	0.000	-31.030

Traceless
	x	y	z
x	-2.814	-4.239	0.000
y	-4.239	-0.034	0.000
z	0.000	0.000	2.848

Polar
3z²-r²	5.696
x²-y²	-1.853
xy	-4.239
xz	0.000
yz	0.000

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

	x	y	z
x	4.907	-0.051	0.000
y	-0.051	4.939	0.000
z	0.000	0.000	2.341

<r²> (average value of r²) Å²

<r²>	173.008
(<r²>)^1/2	13.153

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

using model chemistry: BLYP/STO-3G

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: BLYP/STO-3G

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

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