CCCBDB calculation results Page

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

Energy calculated at HF/CEP-31G

	hartrees
Energy at 0K	-40.976066
Energy at 298.15K	-40.991567
Nuclear repulsion energy	150.611580

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/CEP-31G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3302	2976	0.00
2	A_g	3274	2951	0.00
3	A_g	3203	2887	0.00
4	A_g	3180	2866	0.00
5	A_g	1665	1501	0.00
6	A_g	1639	1477	0.00
7	A_g	1568	1414	0.00
8	A_g	1518	1368	0.00
9	A_g	1332	1200	0.00
10	A_g	1308	1179	0.00
11	A_g	1035	933	0.00
12	A_g	813	733	0.00
13	A_g	534	482	0.00
14	A_g	414	373	0.00
15	A_g	250	226	0.00
16	A_u	3298	2973	146.65
17	A_u	3262	2940	0.05
18	A_u	3193	2879	92.47
19	A_u	1648	1485	4.26
20	A_u	1622	1462	3.12
21	A_u	1552	1399	11.51
22	A_u	1465	1321	2.76
23	A_u	1174	1059	4.40
24	A_u	1064	959	0.12
25	A_u	1021	920	2.70
26	A_u	328	296	0.01
27	A_u	211	190	0.02
28	A_u	61	55	0.00
29	B_g	3280	2956	0.00
30	B_g	3262	2941	0.00
31	B_g	3191	2876	0.00
32	B_g	1630	1470	0.00
33	B_g	1628	1468	0.00
34	B_g	1548	1395	0.00
35	B_g	1488	1341	0.00
36	B_g	1273	1148	0.00
37	B_g	1046	943	0.00
38	B_g	1016	916	0.00
39	B_g	456	411	0.00
40	B_g	208	187	0.00
41	B_u	3288	2964	212.64
42	B_u	3277	2954	387.36
43	B_u	3196	2881	110.84
44	B_u	3193	2879	77.55
45	B_u	1647	1485	31.12
46	B_u	1640	1478	12.87
47	B_u	1564	1410	17.77
48	B_u	1438	1296	4.10
49	B_u	1289	1162	10.65
50	B_u	1101	992	7.89
51	B_u	934	842	1.15
52	B_u	439	395	0.09
53	B_u	377	340	0.10
54	B_u	229	206	0.03

Unscaled Zero Point Vibrational Energy (zpe) 44284.7 cm^-1
Scaled (by 0.9014) Zero Point Vibrational Energy (zpe) 39918.2 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/CEP-31G

A	B	C
0.13883	0.09439	0.06147

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

Geometric Data calculated at HF/CEP-31G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.780	0.000
C2	0.000	-0.780	0.000
H3	-1.043	1.111	0.000
H4	1.043	-1.111	0.000
C5	0.689	1.363	1.261
C6	0.689	1.363	-1.261
C7	-0.689	-1.363	1.261
C8	-0.689	-1.363	-1.261
H9	1.713	0.991	1.348
H10	1.713	0.991	-1.348
H11	-1.713	-0.991	1.348
H12	-1.713	-0.991	-1.348
H13	0.736	2.451	1.201
H14	0.160	1.110	2.177
H15	0.736	2.451	-1.201
H16	0.160	1.110	-2.177
H17	-0.736	-2.451	1.201
H18	-0.160	-1.110	2.177
H19	-0.736	-2.451	-1.201
H20	-0.160	-1.110	-2.177

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		1.5607	1.0941	2.1600	1.5506	1.5506	2.5806	2.5806	2.1901	2.1901	2.8091	2.8091	2.1853	2.2079	2.1853	2.2079	3.5252	2.8879	3.5252	2.8879
C2	1.5607		2.1600	1.0941	2.5806	2.5806	1.5506	1.5506	2.8091	2.8091	2.1901	2.1901	3.5252	2.8879	3.5252	2.8879	2.1853	2.2079	2.1853	2.2079
H3	1.0941	2.1600		3.0479	2.1572	2.1572	2.7995	2.7995	3.0703	3.0703	2.5860	2.5860	2.5304	2.4875	2.5304	2.4875	3.7718	3.2332	3.7718	3.2332
H4	2.1600	1.0941	3.0479		2.7995	2.7995	2.1572	2.1572	2.5860	2.5860	3.0703	3.0703	3.7718	3.2332	3.7718	3.2332	2.5304	2.4875	2.5304	2.4875
C5	1.5506	2.5806	2.1572	2.7995		2.5213	3.0553	3.9613	1.0926	2.8271	3.3650	4.2570	1.0906	1.0883	2.6915	3.4876	4.0727	2.7711	4.7583	4.3195
C6	1.5506	2.5806	2.1572	2.7995	2.5213		3.9613	3.0553	2.8271	1.0926	4.2570	3.3650	2.6915	3.4876	1.0906	1.0883	4.7583	4.3195	4.0727	2.7711
C7	2.5806	1.5506	2.7995	2.1572	3.0553	3.9613		2.5213	3.3650	4.2570	1.0926	2.8271	4.0727	2.7711	4.7583	4.3195	1.0906	1.0883	2.6915	3.4876
C8	2.5806	1.5506	2.7995	2.1572	3.9613	3.0553	2.5213		4.2570	3.3650	2.8271	1.0926	4.7583	4.3195	4.0727	2.7711	2.6915	3.4876	1.0906	1.0883
H9	2.1901	2.8091	3.0703	2.5860	1.0926	2.8271	3.3650	4.2570		2.6966	3.9583	4.7895	1.7626	1.7643	3.0955	3.8542	4.2275	2.9345	4.9343	4.5115
H10	2.1901	2.8091	3.0703	2.5860	2.8271	1.0926	4.2570	3.3650	2.6966		4.7895	3.9583	3.0955	3.8542	1.7626	1.7643	4.9343	4.5115	4.2275	2.9345
H11	2.8091	2.1901	2.5860	3.0703	3.3650	4.2570	1.0926	2.8271	3.9583	4.7895		2.6966	4.2275	2.9345	4.9343	4.5115	1.7626	1.7643	3.0955	3.8542
H12	2.8091	2.1901	2.5860	3.0703	4.2570	3.3650	2.8271	1.0926	4.7895	3.9583	2.6966		4.9343	4.5115	4.2275	2.9345	3.0955	3.8542	1.7626	1.7643
H13	2.1853	3.5252	2.5304	3.7718	1.0906	2.6915	4.0727	4.7583	1.7626	3.0955	4.2275	4.9343		1.7563	2.4014	3.6798	5.1189	3.8000	5.6542	4.9897
H14	2.2079	2.8879	2.4875	3.2332	1.0883	3.4876	2.7711	4.3195	1.7643	3.8542	2.9345	4.5115	1.7563		3.6798	4.3545	3.8000	2.2431	4.9897	4.8983
H15	2.1853	3.5252	2.5304	3.7718	2.6915	1.0906	4.7583	4.0727	3.0955	1.7626	4.9343	4.2275	2.4014	3.6798		1.7563	5.6542	4.9897	5.1189	3.8000
H16	2.2079	2.8879	2.4875	3.2332	3.4876	1.0883	4.3195	2.7711	3.8542	1.7643	4.5115	2.9345	3.6798	4.3545	1.7563		4.9897	4.8983	3.8000	2.2431
H17	3.5252	2.1853	3.7718	2.5304	4.0727	4.7583	1.0906	2.6915	4.2275	4.9343	1.7626	3.0955	5.1189	3.8000	5.6542	4.9897		1.7563	2.4014	3.6798
H18	2.8879	2.2079	3.2332	2.4875	2.7711	4.3195	1.0883	3.4876	2.9345	4.5115	1.7643	3.8542	3.8000	2.2431	4.9897	4.8983	1.7563		3.6798	4.3545
H19	3.5252	2.1853	3.7718	2.5304	4.7583	4.0727	2.6915	1.0906	4.9343	4.2275	3.0955	1.7626	5.6542	4.9897	5.1189	3.8000	2.4014	3.6798		1.7563
H20	2.8879	2.2079	3.2332	2.4875	4.3195	2.7711	3.4876	1.0883	4.5115	2.9345	3.8542	1.7643	4.9897	4.8983	3.8000	2.2431	3.6798	4.3545	1.7563

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	107.603	C1	C2	C7	112.081
C1	C2	C8	112.081	C1	C5	H9	110.718
C1	C5	H13	110.454	C1	C5	H14	112.397
C1	C6	H10	110.718	C1	C6	H15	110.454
C1	C6	H16	112.397	C2	C1	H3	107.603
C2	C1	C5	112.081	C2	C1	C6	112.081
C2	C7	H11	110.718	C2	C7	H17	110.454
C2	C7	H18	112.397	C2	C8	H12	110.718
C2	C8	H19	110.454	C2	C8	H20	112.397
H3	C1	C5	108.066	H3	C1	C6	108.066
H4	C2	C7	108.066	H4	C2	C8	108.066
C5	C1	C6	108.783	C7	C2	C8	108.783
H9	C5	H13	107.678	H9	C5	H14	107.991
H10	C6	H15	107.678	H10	C6	H16	107.991
H11	C7	H17	107.678	H11	C7	H18	107.991
H12	C8	H19	107.678	H12	C8	H20	107.991
H13	C5	H14	107.419	H15	C6	H16	107.419
H17	C7	H18	107.419	H19	C8	H20	107.419

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G Charges (e)

Number	Element	Mulliken
1	C	0.013
2	C	0.013
3	H	0.073
4	H	0.073
5	C	-0.363
6	C	-0.363
7	C	-0.363
8	C	-0.363
9	H	0.085
10	H	0.085
11	H	0.085
12	H	0.085
13	H	0.118
14	H	0.117
15	H	0.118
16	H	0.117
17	H	0.118
18	H	0.117
19	H	0.118
20	H	0.117

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	-41.920	-0.674	0.000
y	-0.674	-42.146	0.000
z	0.000	0.000	-42.958

Traceless
	x	y	z
x	0.632	-0.674	0.000
y	-0.674	0.293	0.000
z	0.000	0.000	-0.925

Polar
3z²-r²	-1.851
x²-y²	0.226
xy	-0.674
xz	0.000
yz	0.000

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

	x	y	z
x	8.342	0.697	0.000
y	0.697	9.289	0.000
z	0.000	0.000	9.364

<r²> (average value of r²) Å²

<r²>	177.632
(<r²>)^1/2	13.328

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

using model chemistry: HF/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: HF/CEP-31G

States and conformations

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