CCCBDB calculation results Page

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

Energy calculated at HF/3-21G*

	hartrees
Energy at 0K	-234.069710
Energy at 298.15K	-234.085311
Nuclear repulsion energy	262.426042

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/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3282	2962	0.00
2	A_g	3250	2934	0.00
3	A_g	3197	2886	0.00
4	A_g	3184	2874	0.00
5	A_g	1701	1536	0.00
6	A_g	1674	1511	0.00
7	A_g	1587	1433	0.00
8	A_g	1507	1360	0.00
9	A_g	1334	1204	0.00
10	A_g	1306	1179	0.00
11	A_g	1008	909	0.00
12	A_g	807	728	0.00
13	A_g	533	481	0.00
14	A_g	422	381	0.00
15	A_g	260	235	0.00
16	A_u	3281	2961	70.34
17	A_u	3239	2924	0.20
18	A_u	3190	2879	33.70
19	A_u	1683	1519	5.98
20	A_u	1656	1495	1.79
21	A_u	1568	1415	15.42
22	A_u	1473	1330	2.35
23	A_u	1154	1042	4.35
24	A_u	1056	953	1.40
25	A_u	1031	931	2.35
26	A_u	336	303	0.02
27	A_u	222	201	0.02
28	A_u	60	55	0.00
29	B_g	3262	2945	0.00
30	B_g	3240	2924	0.00
31	B_g	3189	2878	0.00
32	B_g	1664	1502	0.00
33	B_g	1663	1501	0.00
34	B_g	1560	1408	0.00
35	B_g	1487	1342	0.00
36	B_g	1263	1140	0.00
37	B_g	1042	941	0.00
38	B_g	1023	924	0.00
39	B_g	462	417	0.00
40	B_g	224	202	0.00
41	B_u	3267	2949	83.69
42	B_u	3253	2936	157.94
43	B_u	3200	2889	58.44
44	B_u	3191	2880	16.66
45	B_u	1684	1520	28.07
46	B_u	1676	1513	11.50
47	B_u	1579	1426	19.10
48	B_u	1450	1308	3.51
49	B_u	1294	1168	11.14
50	B_u	1122	1013	11.30
51	B_u	906	817	1.63
52	B_u	447	403	0.28
53	B_u	377	341	0.30
54	B_u	242	218	0.02

Unscaled Zero Point Vibrational Energy (zpe) 44384.4 cm^-1
Scaled (by 0.9026) Zero Point Vibrational Energy (zpe) 40061.3 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 HF/3-21G*

A	B	C
0.14070	0.09569	0.06240

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

Geometric Data calculated at HF/3-21G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.775	0.000
C2	0.000	-0.775	0.000
H3	-1.035	1.107	0.000
H4	1.035	-1.107	0.000
C5	0.699	1.347	1.252
C6	0.699	1.347	-1.252
C7	-0.699	-1.347	1.252
C8	-0.699	-1.347	-1.252
H9	1.717	0.973	1.315
H10	1.717	0.973	-1.315
H11	-1.717	-0.973	1.315
H12	-1.717	-0.973	-1.315
H13	0.741	2.429	1.197
H14	0.181	1.083	2.165
H15	0.741	2.429	-1.197
H16	0.181	1.083	-2.165
H17	-0.741	-2.429	1.197
H18	-0.181	-1.083	2.165
H19	-0.741	-2.429	-1.197
H20	-0.181	-1.083	-2.165

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		1.5507	1.0871	2.1483	1.5440	1.5440	2.5614	2.5614	2.1718	2.1718	2.7813	2.7813	2.1720	2.1938	2.1720	2.1938	3.5003	2.8585	3.5003	2.8585
C2	1.5507		2.1483	1.0871	2.5614	2.5614	1.5440	1.5440	2.7813	2.7813	2.1718	2.1718	3.5003	2.8585	3.5003	2.8585	2.1720	2.1938	2.1720	2.1938
H3	1.0871	2.1483		3.0314	2.1529	2.1529	2.7752	2.7752	3.0534	3.0534	2.5537	2.5537	2.5173	2.4828	2.5173	2.4828	3.7450	3.1956	3.7450	3.1956
H4	2.1483	1.0871	3.0314		2.7752	2.7752	2.1529	2.1529	2.5537	2.5537	3.0534	3.0534	3.7450	3.1956	3.7450	3.1956	2.5173	2.4828	2.5173	2.4828
C5	1.5440	2.5614	2.1529	2.7752		2.5046	3.0350	3.9350	1.0860	2.7865	3.3507	4.2205	1.0848	1.0821	2.6783	3.4661	4.0418	2.7404	4.7257	4.2840
C6	1.5440	2.5614	2.1529	2.7752	2.5046		3.9350	3.0350	2.7865	1.0860	4.2205	3.3507	2.6783	3.4661	1.0848	1.0821	4.7257	4.2840	4.0418	2.7404
C7	2.5614	1.5440	2.7752	2.1529	3.0350	3.9350		2.5046	3.3507	4.2205	1.0860	2.7865	4.0418	2.7404	4.7257	4.2840	1.0848	1.0821	2.6783	3.4661
C8	2.5614	1.5440	2.7752	2.1529	3.9350	3.0350	2.5046		4.2205	3.3507	2.7865	1.0860	4.7257	4.2840	4.0418	2.7404	2.6783	3.4661	1.0848	1.0821
H9	2.1718	2.7813	3.0534	2.5537	1.0860	2.7865	3.3507	4.2205		2.6292	3.9480	4.7434	1.7568	1.7595	3.0629	3.8050	4.1995	2.9246	4.8919	4.4649
H10	2.1718	2.7813	3.0534	2.5537	2.7865	1.0860	4.2205	3.3507	2.6292		4.7434	3.9480	3.0629	3.8050	1.7568	1.7595	4.8919	4.4649	4.1995	2.9246
H11	2.7813	2.1718	2.5537	3.0534	3.3507	4.2205	1.0860	2.7865	3.9480	4.7434		2.6292	4.1995	2.9246	4.8919	4.4649	1.7568	1.7595	3.0629	3.8050
H12	2.7813	2.1718	2.5537	3.0534	4.2205	3.3507	2.7865	1.0860	4.7434	3.9480	2.6292		4.8919	4.4649	4.1995	2.9246	3.0629	3.8050	1.7568	1.7595
H13	2.1720	3.5003	2.5173	3.7450	1.0848	2.6783	4.0418	4.7257	1.7568	3.0629	4.1995	4.8919		1.7500	2.3942	3.6643	5.0796	3.7578	5.6156	4.9483
H14	2.1938	2.8585	2.4828	3.1956	1.0821	3.4661	2.7404	4.2840	1.7595	3.8050	2.9246	4.4649	1.7500		3.6643	4.3291	3.7578	2.1958	4.9483	4.8542
H15	2.1720	3.5003	2.5173	3.7450	2.6783	1.0848	4.7257	4.0418	3.0629	1.7568	4.8919	4.1995	2.3942	3.6643		1.7500	5.6156	4.9483	5.0796	3.7578
H16	2.1938	2.8585	2.4828	3.1956	3.4661	1.0821	4.2840	2.7404	3.8050	1.7595	4.4649	2.9246	3.6643	4.3291	1.7500		4.9483	4.8542	3.7578	2.1958
H17	3.5003	2.1720	3.7450	2.5173	4.0418	4.7257	1.0848	2.6783	4.1995	4.8919	1.7568	3.0629	5.0796	3.7578	5.6156	4.9483		1.7500	2.3942	3.6643
H18	2.8585	2.1938	3.1956	2.4828	2.7404	4.2840	1.0821	3.4661	2.9246	4.4649	1.7595	3.8050	3.7578	2.1958	4.9483	4.8542	1.7500		3.6643	4.3291
H19	3.5003	2.1720	3.7450	2.5173	4.7257	4.0418	2.6783	1.0848	4.8919	4.1995	3.0629	1.7568	5.6156	4.9483	5.0796	3.7578	2.3942	3.6643		1.7500
H20	2.8585	2.1938	3.1956	2.4828	4.2840	2.7404	3.4661	1.0821	4.4649	2.9246	3.8050	1.7595	4.9483	4.8542	3.7578	2.1958	3.6643	4.3291	1.7500

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	107.762	C1	C2	C7	111.719
C1	C2	C8	111.719	C1	C5	H9	110.114
C1	C5	H13	110.208	C1	C5	H14	112.112
C1	C6	H10	110.114	C1	C6	H15	110.208
C1	C6	H16	112.112	C2	C1	H3	107.762
C2	C1	C5	111.719	C2	C1	C6	111.719
C2	C7	H11	110.114	C2	C7	H17	110.208
C2	C7	H18	112.112	C2	C8	H12	110.114
C2	C8	H19	110.208	C2	C8	H20	112.112
H3	C1	C5	108.572	H3	C1	C6	108.572
H4	C2	C7	108.572	H4	C2	C8	108.572
C5	C1	C6	108.405	C7	C2	C8	108.405
H9	C5	H13	108.057	H9	C5	H14	108.495
H10	C6	H15	108.057	H10	C6	H16	108.495
H11	C7	H17	108.057	H11	C7	H18	108.495
H12	C8	H19	108.057	H12	C8	H20	108.495
H13	C5	H14	107.733	H15	C6	H16	107.733
H17	C7	H18	107.733	H19	C8	H20	107.733

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/3-21G* Charges (e)

Number	Element	Mulliken	CHELPG
1	C	-0.279	0.305
2	C	-0.279	0.305
3	H	0.208	-0.051
4	H	0.208	-0.051
5	C	-0.558	-0.374
6	C	-0.558	-0.374
7	C	-0.558	-0.374
8	C	-0.558	-0.374
9	H	0.193	0.079
10	H	0.193	0.079
11	H	0.193	0.079
12	H	0.193	0.079
13	H	0.197	0.088
14	H	0.202	0.079
15	H	0.197	0.088
16	H	0.202	0.079
17	H	0.197	0.088
18	H	0.202	0.079
19	H	0.197	0.088
20	H	0.202	0.079

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	0.000	0.000	0.000	0.000
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-42.325	-0.370	0.000
y	-0.370	-42.363	0.000
z	0.000	0.000	-42.782

Traceless
	x	y	z
x	0.248	-0.370	0.000
y	-0.370	0.190	0.000
z	0.000	0.000	-0.438

Polar
3z²-r²	-0.876
x²-y²	0.038
xy	-0.370
xz	0.000
yz	0.000

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

	x	y	z
x	8.174	0.579	0.000
y	0.579	9.200	0.000
z	0.000	0.000	8.910

<r²> (average value of r²) Å²

<r²>	208.849
(<r²>)^1/2	14.452

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

using model chemistry: HF/3-21G*

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/3-21G*

States and conformations

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