CCCBDB calculation results Page

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

Conformer 1 (C2H)

Jump to S1C2 S1C3

Energy calculated at HF/daug-cc-pVTZ

	hartrees
Energy at 0K	-304.806032
Energy at 298.15K	-304.812470
HF Energy	-304.806032
Nuclear repulsion energy	228.172610

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 HF/daug-cc-pVTZ

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3282	2969	0.00
2	A_g	3184	2880	0.00
3	A_g	2004	1812	0.00
4	A_g	1577	1427	0.00
5	A_g	1535	1388	0.00
6	A_g	1406	1272	0.00
7	A_g	1108	1003	0.00
8	A_g	742	672	0.00
9	A_g	570	516	0.00
10	A_g	386	349	0.00
11	A_u	3243	2934	15.54
12	A_u	1584	1433	17.46
13	A_u	1063	962	4.62
14	A_u	394	357	12.79
15	A_u	143	129	0.13
16	A_u	49	45	13.39
17	B_g	3243	2934	0.00
18	B_g	1588	1437	0.00
19	B_g	1185	1072	0.00
20	B_g	682	617	0.00
21	B_g	145	131	0.00
22	B_u	3283	2970	22.90
23	B_u	3183	2880	3.99
24	B_u	1981	1792	389.58
25	B_u	1577	1427	27.92
26	B_u	1523	1378	36.93
27	B_u	1229	1112	79.91
28	B_u	982	888	21.19
29	B_u	589	533	59.17
30	B_u	255	231	18.76

Unscaled Zero Point Vibrational Energy (zpe) 21858.3 cm^-1
Scaled (by 0.9046) Zero Point Vibrational Energy (zpe) 19773.0 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 HF/daug-cc-pVTZ

A	B	C
0.18245	0.11271	0.07147

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

Geometric Data calculated at HF/daug-cc-pVTZ

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.084	0.767	0.000
C2	0.084	-0.767	0.000
C3	1.175	1.588	0.000
C4	-1.175	-1.588	0.000
O5	-1.175	1.227	0.000
O6	1.175	-1.227	0.000
H7	0.916	2.635	0.000
H8	-0.916	-2.635	0.000
H9	1.772	1.346	0.870
H10	1.772	1.346	-0.870
H11	-1.772	-1.346	0.870
H12	-1.772	-1.346	-0.870

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5428	1.5026	2.5952	1.1842	2.3576	2.1192	3.5025	2.1299	2.1299	2.8411	2.8411
C2	1.5428		2.5952	1.5026	2.3576	1.1842	3.5025	2.1192	2.8411	2.8411	2.1299	2.1299
C3	1.5026	2.5952		3.9503	2.3773	2.8144	1.0789	4.7124	1.0825	1.0825	4.2484	4.2484
C4	2.5952	1.5026	3.9503		2.8144	2.3773	4.7124	1.0789	4.2484	4.2484	1.0825	1.0825
O5	1.1842	2.3576	2.3773	2.8144		3.3972	2.5214	3.8706	3.0752	3.0752	2.7807	2.7807
O6	2.3576	1.1842	2.8144	2.3773	3.3972		3.8706	2.5214	2.7807	2.7807	3.0752	3.0752
H7	2.1192	3.5025	1.0789	4.7124	2.5214	3.8706		5.5801	1.7751	1.7751	4.8822	4.8822
H8	3.5025	2.1192	4.7124	1.0789	3.8706	2.5214	5.5801		4.8822	4.8822	1.7751	1.7751
H9	2.1299	2.8411	1.0825	4.2484	3.0752	2.7807	1.7751	4.8822		1.7395	4.4509	4.7788
H10	2.1299	2.8411	1.0825	4.2484	3.0752	2.7807	1.7751	4.8822	1.7395		4.7788	4.4509
H11	2.8411	2.1299	4.2484	1.0825	2.7807	3.0752	4.8822	1.7751	4.4509	4.7788		1.7395
H12	2.8411	2.1299	4.2484	1.0825	2.7807	3.0752	4.8822	1.7751	4.7788	4.4509	1.7395

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	116.887	C1	C2	O6	119.078
C1	C3	H7	109.255	C1	C3	H9	109.892
C1	C3	H10	109.892	C2	C1	C3	116.887
C2	C1	O5	119.078	C2	C4	H8	109.255
C2	C4	H11	109.892	C2	C4	H12	109.892
C3	C1	O5	124.035	C4	C2	O6	124.035
H7	C3	H9	110.427	H7	C3	H10	110.427
H8	C4	H11	110.427	H8	C4	H12	110.427
H9	C3	H10	106.924	H11	C4	H12	106.924

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/daug-cc-pVTZ Charges (e)

Number	Element	Mulliken
1	C	1.348
2	C	1.348
3	C	-1.240
4	C	-1.240
5	O	-1.253
6	O	-1.253
7	H	0.386
8	H	0.386
9	H	0.380
10	H	0.380
11	H	0.380
12	H	0.380

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	-39.414	8.120	0.000
y	8.120	-36.907	0.000
z	0.000	0.000	-33.699

Traceless
	x	y	z
x	-4.111	8.120	0.000
y	8.120	-0.351	0.000
z	0.000	0.000	4.462

Polar
3z²-r²	8.924
x²-y²	-2.507
xy	8.120
xz	0.000
yz	0.000

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

	x	y	z
x	8.587	0.027	0.000
y	0.027	8.016	0.000
z	0.000	0.000	5.702

<r²> (average value of r²) Å²

<r²>	161.430
(<r²>)^1/2	12.705

	hartrees
Energy at 0K	-304.803724
Energy at 298.15K
HF Energy	-304.803724
Nuclear repulsion energy	227.763811

Conformer 3 (CI)

Jump to S1C1 S1C2

Energy calculated at HF/daug-cc-pVTZ

	hartrees
Energy at 0K	-304.806030
Energy at 298.15K	-304.812470
HF Energy	-304.806030
Nuclear repulsion energy	228.183282

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 HF/daug-cc-pVTZ

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3283	2970	0.00
2	A_g	3243	2933	0.00
3	A_g	3184	2880	0.00
4	A_g	2002	1811	0.00
5	A_g	1588	1437	0.00
6	A_g	1578	1427	0.00
7	A_g	1535	1389	0.00
8	A_g	1407	1272	0.00
9	A_g	1185	1072	0.00
10	A_g	1108	1003	0.00
11	A_g	743	672	0.00
12	A_g	682	617	0.00
13	A_g	571	516	0.00
14	A_g	386	349	0.00
15	A_g	145	131	0.00
16	A_u	3283	2970	22.98
17	A_u	3243	2933	15.50
18	A_u	3183	2880	3.90
19	A_u	1979	1790	389.55
20	A_u	1584	1433	17.47
21	A_u	1577	1427	28.04
22	A_u	1524	1378	37.06
23	A_u	1229	1112	80.05
24	A_u	1063	962	4.63
25	A_u	983	889	20.92
26	A_u	589	533	59.25
27	A_u	395	357	12.83
28	A_u	256	231	18.71
29	A_u	143	129	0.12
30	A_u	50	45	13.37

Unscaled Zero Point Vibrational Energy (zpe) 21859.6 cm^-1
Scaled (by 0.9046) Zero Point Vibrational Energy (zpe) 19774.2 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 HF/daug-cc-pVTZ

A	B	C
0.18243	0.11275	0.07149

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

Geometric Data calculated at HF/daug-cc-pVTZ

Point Group is C_i

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.016	-0.000	-0.771
C2	-0.016	0.000	0.771
C3	1.368	-0.000	-1.424
C4	-1.368	0.000	1.424
O5	-1.008	-0.000	-1.367
O6	1.008	0.000	1.367
H7	1.930	0.870	-1.108
H8	-1.930	-0.870	1.108
H9	1.930	-0.870	-1.107
H10	1.246	-0.000	-2.496
H11	-1.930	0.870	1.107
H12	-1.246	0.000	2.496

Atom - Atom Distances (Å)

	C1	C2	C3	C4	O5	O6	H7	H8	H9	H10	H11	H12
C1		1.5429	1.5020	2.5949	1.1844	2.3575	2.1297	2.8413	2.1298	2.1185	2.8412	3.5021
C2	1.5429		2.5949	1.5020	2.3575	1.1844	2.8413	2.1297	2.8412	3.5021	2.1298	2.1185
C3	1.5020	2.5949		3.9494	2.3773	2.8139	1.0826	4.2480	1.0826	1.0788	4.2480	4.7115
C4	2.5949	1.5020	3.9494		2.8139	2.3773	4.2480	1.0826	4.2480	4.7115	1.0826	1.0788
O5	1.1844	2.3575	2.3773	2.8139		3.3972	3.0754	2.7805	3.0755	2.5213	2.7803	3.8699
O6	2.3575	1.1844	2.8139	2.3773	3.3972		2.7805	3.0754	2.7803	3.8699	3.0755	2.5213
H7	2.1297	2.8413	1.0826	4.2480	3.0754	2.7805		4.7788	1.7395	1.7749	4.4509	4.8817
H8	2.8413	2.1297	4.2480	1.0826	2.7805	3.0754	4.7788		4.4509	4.8817	1.7395	1.7749
H9	2.1298	2.8412	1.0826	4.2480	3.0755	2.7803	1.7395	4.4509		1.7750	4.7787	4.8816
H10	2.1185	3.5021	1.0788	4.7115	2.5213	3.8699	1.7749	4.8817	1.7750		4.8816	5.5790
H11	2.8412	2.1298	4.2480	1.0826	2.7803	3.0755	4.4509	1.7395	4.7787	4.8816		1.7750
H12	3.5021	2.1185	4.7115	1.0788	3.8699	2.5213	4.8817	1.7749	4.8816	5.5790	1.7750

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	116.894	C1	C2	O6	119.045
C1	C3	H7	109.917	C1	C3	H9	109.918
C1	C3	H10	109.248	C2	C1	C3	116.894
C2	C1	O5	119.045	C2	C4	H8	109.917
C2	C4	H11	109.918	C2	C4	H12	109.248
C3	C1	O5	124.062	C4	C2	O6	124.062
H7	C3	H9	106.911	H7	C3	H10	110.412
H8	C4	H11	106.911	H8	C4	H12	110.412
H9	C3	H10	110.413	H11	C4	H12	110.413

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/daug-cc-pVTZ Charges (e)

Number	Element	Mulliken
1	C	1.439
2	C	1.439
3	C	-1.273
4	C	-1.273
5	O	-1.263
6	O	-1.263
7	H	0.355
8	H	0.355
9	H	0.355
10	H	0.387
11	H	0.355
12	H	0.387

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	-37.303	-0.001	-8.179
y	-0.001	-33.699	-0.000
z	-8.179	-0.000	-39.014

Traceless
	x	y	z
x	-0.947	-0.001	-8.179
y	-0.001	4.460	-0.000
z	-8.179	-0.000	-3.513

Polar
3z²-r²	-7.027
x²-y²	-3.604
xy	-0.001
xz	-8.179
yz	-0.000

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

	x	y	z
x	8.584	0.000	0.049
y	0.000	5.702	0.000
z	0.049	0.000	8.017

<r²> (average value of r²) Å²

<r²>	161.403
(<r²>)^1/2	12.704

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

using model chemistry: HF/daug-cc-pVTZ

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

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

using model chemistry: HF/daug-cc-pVTZ

States and conformations

Conformer 1 (C2H)

Conformer 2 (C2)

Conformer 3 (CI)

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