CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C2H	¹A_g

Energy calculated at MP2/CEP-31G*

	hartrees
Energy at 0K	-41.829035
Energy at 298.15K	-41.844147
HF Energy	-41.076273
Nuclear repulsion energy	150.423435

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 MP2/CEP-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3192	3031	0.00
2	A_g	3168	3007	0.00
3	A_g	3076	2920	0.00
4	A_g	3074	2918	0.00
5	A_g	1559	1480	0.00
6	A_g	1530	1453	0.00
7	A_g	1450	1376	0.00
8	A_g	1420	1348	0.00
9	A_g	1247	1183	0.00
10	A_g	1219	1157	0.00
11	A_g	988	938	0.00
12	A_g	781	742	0.00
13	A_g	504	478	0.00
14	A_g	406	385	0.00
15	A_g	238	226	0.00
16	A_u	3191	3029	62.10
17	A_u	3163	3003	0.01
18	A_u	3074	2918	58.99
19	A_u	1539	1461	4.53
20	A_u	1507	1431	2.09
21	A_u	1437	1364	13.03
22	A_u	1361	1292	1.30
23	A_u	1124	1068	1.38
24	A_u	995	944	1.03
25	A_u	946	898	3.40
26	A_u	325	309	0.01
27	A_u	196	186	0.02
28	A_u	60	57	0.00
29	B_g	3177	3017	0.00
30	B_g	3163	3003	0.00
31	B_g	3071	2916	0.00
32	B_g	1517	1440	0.00
33	B_g	1516	1440	0.00
34	B_g	1435	1363	0.00
35	B_g	1375	1305	0.00
36	B_g	1202	1141	0.00
37	B_g	986	936	0.00
38	B_g	940	892	0.00
39	B_g	432	410	0.00
40	B_g	193	183	0.00
41	B_u	3181	3020	89.96
42	B_u	3169	3009	169.14
43	B_u	3086	2930	52.53
44	B_u	3072	2917	57.81
45	B_u	1537	1460	33.69
46	B_u	1529	1452	10.14
47	B_u	1445	1372	18.02
48	B_u	1320	1253	3.27
49	B_u	1201	1140	8.23
50	B_u	1019	968	9.59
51	B_u	901	856	2.12
52	B_u	415	394	0.02
53	B_u	353	336	0.13
54	B_u	216	205	0.02

Unscaled Zero Point Vibrational Energy (zpe) 42108.1 cm^-1
Scaled (by 0.9494) Zero Point Vibrational Energy (zpe) 39977.5 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 MP2/CEP-31G*

A	B	C
0.13856	0.09524	0.06190

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

Geometric Data calculated at MP2/CEP-31G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.776	0.000
C2	0.000	-0.776	0.000
H3	-1.059	1.109	0.000
H4	1.059	-1.109	0.000
C5	0.690	1.352	1.260
C6	0.690	1.352	-1.260
C7	-0.690	-1.352	1.260
C8	-0.690	-1.352	-1.260
H9	1.721	0.960	1.348
H10	1.721	0.960	-1.348
H11	-1.721	-0.960	1.348
H12	-1.721	-0.960	-1.348
H13	0.750	2.454	1.195
H14	0.146	1.102	2.186
H15	0.750	2.454	-1.195
H16	0.146	1.102	-2.186
H17	-0.750	-2.454	1.195
H18	-0.146	-1.102	2.186
H19	-0.750	-2.454	-1.195
H20	-0.146	-1.102	-2.186

Atom - Atom Distances (Å)

	C1	C2	H3	H4	C5	C6	C7	C8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18	H19	H20
C1		1.5521	1.1100	2.1619	1.5474	1.5474	2.5676	2.5676	2.1936	2.1936	2.7913	2.7913	2.1924	2.2149	2.1924	2.2149	3.5248	2.8857	3.5248	2.8857
C2	1.5521		2.1619	1.1100	2.5676	2.5676	1.5474	1.5474	2.7913	2.7913	2.1936	2.1936	3.5248	2.8857	3.5248	2.8857	2.1924	2.2149	2.1924	2.2149
H3	1.1100	2.1619		3.0664	2.1689	2.1689	2.7893	2.7893	3.0930	3.0930	2.5562	2.5562	2.5516	2.4959	2.5516	2.4959	3.7706	3.2405	3.7706	3.2405
H4	2.1619	1.1100	3.0664		2.7893	2.7893	2.1689	2.1689	2.5562	2.5562	3.0930	3.0930	3.7706	3.2405	3.7706	3.2405	2.5516	2.4959	2.5516	2.4959
C5	1.5474	2.5676	2.1689	2.7893		2.5192	3.0362	3.9453	1.1068	2.8312	3.3415	4.2375	1.1052	1.1029	2.6912	3.4971	4.0701	2.7534	4.7526	4.3122
C6	1.5474	2.5676	2.1689	2.7893	2.5192		3.9453	3.0362	2.8312	1.1068	4.2375	3.3415	2.6912	3.4971	1.1052	1.1029	4.7526	4.3122	4.0701	2.7534
C7	2.5676	1.5474	2.7893	2.1689	3.0362	3.9453		2.5192	3.3415	4.2375	1.1068	2.8312	4.0701	2.7534	4.7526	4.3122	1.1052	1.1029	2.6912	3.4971
C8	2.5676	1.5474	2.7893	2.1689	3.9453	3.0362	2.5192		4.2375	3.3415	2.8312	1.1068	4.7526	4.3122	4.0701	2.7534	2.6912	3.4971	1.1052	1.1029
H9	2.1936	2.7913	3.0930	2.5562	1.1068	2.8312	3.3415	4.2375		2.6956	3.9411	4.7747	1.7884	1.7899	3.1050	3.8715	4.2171	2.9051	4.9221	4.4971
H10	2.1936	2.7913	3.0930	2.5562	2.8312	1.1068	4.2375	3.3415	2.6956		4.7747	3.9411	3.1050	3.8715	1.7884	1.7899	4.9221	4.4971	4.2171	2.9051
H11	2.7913	2.1936	2.5562	3.0930	3.3415	4.2375	1.1068	2.8312	3.9411	4.7747		2.6956	4.2171	2.9051	4.9221	4.4971	1.7884	1.7899	3.1050	3.8715
H12	2.7913	2.1936	2.5562	3.0930	4.2375	3.3415	2.8312	1.1068	4.7747	3.9411	2.6956		4.9221	4.4971	4.2171	2.9051	3.1050	3.8715	1.7884	1.7899
H13	2.1924	3.5248	2.5516	3.7706	1.1052	2.6912	4.0701	4.7526	1.7884	3.1050	4.2171	4.9221		1.7816	2.3901	3.6910	5.1322	3.7989	5.6615	4.9881
H14	2.2149	2.8857	2.4959	3.2405	1.1029	3.4971	2.7534	4.3122	1.7899	3.8715	2.9051	4.4971	1.7816		3.6910	4.3718	3.7989	2.2238	4.9881	4.9048
H15	2.1924	3.5248	2.5516	3.7706	2.6912	1.1052	4.7526	4.0701	3.1050	1.7884	4.9221	4.2171	2.3901	3.6910		1.7816	5.6615	4.9881	5.1322	3.7989
H16	2.2149	2.8857	2.4959	3.2405	3.4971	1.1029	4.3122	2.7534	3.8715	1.7899	4.4971	2.9051	3.6910	4.3718	1.7816		4.9881	4.9048	3.7989	2.2238
H17	3.5248	2.1924	3.7706	2.5516	4.0701	4.7526	1.1052	2.6912	4.2171	4.9221	1.7884	3.1050	5.1322	3.7989	5.6615	4.9881		1.7816	2.3901	3.6910
H18	2.8857	2.2149	3.2405	2.4959	2.7534	4.3122	1.1029	3.4971	2.9051	4.4971	1.7899	3.8715	3.7989	2.2238	4.9881	4.9048	1.7816		3.6910	4.3718
H19	3.5248	2.1924	3.7706	2.5516	4.7526	4.0701	2.6912	1.1052	4.9221	4.2171	3.1050	1.7884	5.6615	4.9881	5.1322	3.7989	2.3901	3.6910		1.7816
H20	2.8857	2.2149	3.2405	2.4959	4.3122	2.7534	3.4971	1.1029	4.4971	2.9051	3.8715	1.7899	4.9881	4.9048	3.7989	2.2238	3.6910	4.3718	1.7816

picture of Butane, 2,3-dimethyl- state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H4	107.444	C1	C2	C7	111.864
C1	C2	C8	111.864	C1	C5	H9	110.371
C1	C5	H13	110.367	C1	C5	H14	112.291
C1	C6	H10	110.371	C1	C6	H15	110.367
C1	C6	H16	112.291	C2	C1	H3	107.444
C2	C1	C5	111.864	C2	C1	C6	111.864
C2	C7	H11	110.371	C2	C7	H17	110.367
C2	C7	H18	112.291	C2	C8	H12	110.371
C2	C8	H19	110.367	C2	C8	H20	112.291
H3	C1	C5	108.279	H3	C1	C6	108.279
H4	C2	C7	108.279	H4	C2	C8	108.279
C5	C1	C6	108.976	C7	C2	C8	108.976
H9	C5	H13	107.893	H9	C5	H14	108.192
H10	C6	H15	107.893	H10	C6	H16	108.192
H11	C7	H17	107.893	H11	C7	H18	108.192
H12	C8	H19	107.893	H12	C8	H20	108.192
H13	C5	H14	107.577	H15	C6	H16	107.577
H17	C7	H18	107.577	H19	C8	H20	107.577

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)

using model chemistry: MP2/CEP-31G*

States and conformations

	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 C6H14 (Butane, 2,3-dimethyl-)

using model chemistry: MP2/CEP-31G*

States and conformations

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)