CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C1	¹A

Energy calculated at HF/3-21G*

	hartrees
Energy at 0K	-272.890219
Energy at 298.15K	-272.908004
Nuclear repulsion energy	318.273658

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	3266	2948	50.94
2	A	3260	2942	140.82
3	A	3252	2935	53.15
4	A	3251	2934	56.67
5	A	3248	2932	34.45
6	A	3240	2925	1.66
7	A	3240	2925	2.28
8	A	3217	2903	1.43
9	A	3211	2898	10.65
10	A	3198	2886	53.67
11	A	3194	2883	14.15
12	A	3193	2882	13.27
13	A	3192	2881	20.86
14	A	3187	2877	4.64
15	A	3186	2875	31.05
16	A	3179	2869	7.15
17	A	1685	1521	16.87
18	A	1677	1513	5.96
19	A	1676	1512	3.65
20	A	1673	1510	7.33
21	A	1669	1506	4.47
22	A	1665	1503	1.30
23	A	1663	1501	0.21
24	A	1655	1494	0.08
25	A	1648	1487	0.28
26	A	1583	1428	7.35
27	A	1574	1421	4.42
28	A	1564	1412	9.75
29	A	1521	1373	1.12
30	A	1513	1366	3.68
31	A	1504	1358	2.50
32	A	1481	1337	0.37
33	A	1472	1329	0.44
34	A	1456	1314	0.49
35	A	1427	1288	0.08
36	A	1386	1251	1.02
37	A	1321	1193	0.21
38	A	1303	1176	6.41
39	A	1259	1137	1.32
40	A	1184	1069	8.27
41	A	1155	1042	1.73
42	A	1101	993	0.44
43	A	1062	959	0.46
44	A	1049	947	0.91
45	A	1039	938	1.03
46	A	1016	917	1.02
47	A	995	898	0.66
48	A	957	864	2.74
49	A	882	796	1.10
50	A	844	762	0.15
51	A	797	720	4.81
52	A	520	469	0.41
53	A	468	422	0.15
54	A	442	399	0.10
55	A	328	296	0.03
56	A	323	291	0.01
57	A	277	250	0.00
58	A	258	233	0.00
59	A	251	227	0.01
60	A	152	137	0.00
61	A	140	127	0.03
62	A	89	81	0.00
63	A	64	57	0.00

Unscaled Zero Point Vibrational Energy (zpe) 51139.7 cm^-1
Scaled (by 0.9026) Zero Point Vibrational Energy (zpe) 46158.7 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
0.20336	0.03309	0.03016

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

Geometric Data calculated at HF/3-21G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.822	-0.905	-0.048
C2	-1.639	0.033	-0.360
C3	-0.332	-0.567	0.201
C4	0.945	0.186	-0.220
C5	2.223	-0.510	0.287
C6	3.499	0.245	-0.134
C7	-1.920	1.433	0.220
H8	-3.748	-0.508	-0.453
H9	-2.661	-1.890	-0.472
H10	-2.941	-1.012	1.026
H11	-1.541	0.116	-1.439
H12	-0.396	-0.592	1.286
H13	-0.250	-1.596	-0.138
H14	0.982	0.251	-1.304
H15	0.924	1.201	0.164
H16	2.186	-0.581	1.370
H17	2.257	-1.523	-0.101
H18	4.389	-0.258	0.230
H19	3.565	0.308	-1.215
H20	3.494	1.254	0.263
H21	-1.995	1.378	1.302
H22	-1.137	2.137	-0.033
H23	-2.856	1.823	-0.165

Atom - Atom Distances (Å)

	C1	C2	C3	C4	C5	C6	C7	H8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18	H19	H20	H21	H22	H23
C1		1.5419	2.5258	3.9261	5.0723	6.4259	2.5199	1.0849	1.0850	1.0857	2.1493	2.7867	2.6657	4.1695	4.3026	5.2150	5.1171	7.2453	6.6053	6.6824	2.7781	3.4777	2.7304
C2	1.5419		1.5438	2.5923	3.9535	5.1474	1.5409	2.1789	2.1805	2.1700	1.0864	2.1555	2.1524	2.7940	2.8646	4.2423	4.2030	6.0632	5.2806	5.3128	2.1676	2.1879	2.1735
C3	2.5258	1.5438		1.5411	2.5571	3.9303	2.5534	3.4783	2.7621	2.7726	2.1489	1.0874	1.0870	2.1586	2.1683	2.7756	2.7761	4.7305	4.2372	4.2374	2.7859	2.8308	3.4953
C4	3.9261	2.5923	1.5411		1.5414	2.5562	3.1549	4.7494	4.1686	4.2534	2.7695	2.1618	2.1474	1.0869	1.0846	2.1577	2.1582	3.5010	2.8051	2.8054	3.5186	2.8590	4.1388
C5	5.0723	3.9535	2.5571	1.5414		1.5410	4.5762	6.0165	5.1319	5.2412	4.1881	2.8045	2.7344	2.1569	2.1515	1.0858	1.0857	2.1806	2.1739	2.1741	4.7317	4.2893	5.6077
C6	6.4259	5.1474	3.9303	2.5562	1.5410		5.5588	7.2927	6.5281	6.6636	5.2077	4.2297	4.1764	2.7760	2.7631	2.1611	2.1611	1.0845	1.0850	1.0850	5.7909	5.0082	6.5483
C7	2.5199	1.5409	2.5534	3.1549	4.5762	5.5588		2.7497	3.4740	2.7695	2.1513	2.7495	3.4772	3.4841	2.8536	4.7150	5.1268	6.5308	5.7797	5.4168	1.0858	1.0832	1.0850
H8	1.0849	2.1789	3.4783	4.7494	6.0165	7.2927	2.7497		1.7580	1.7583	2.4962	3.7770	3.6767	4.8648	5.0123	6.2074	6.0997	8.1685	7.3970	7.4872	3.1159	3.7404	2.5124
H9	1.0850	2.1805	2.7621	4.1686	5.1319	6.5281	3.4740	1.7580		1.7590	2.4927	3.1475	2.4519	4.3061	4.7756	5.3476	4.9453	7.2699	6.6438	6.9504	3.7778	4.3283	3.7308
H10	1.0857	2.1700	2.7726	4.2534	5.2412	6.6636	2.7695	1.7583	1.7590		3.0511	2.5928	2.9902	4.7343	4.5362	5.1564	5.3432	7.4113	7.0066	6.8650	2.5855	3.7809	3.0763
H11	2.1493	1.0864	2.1489	2.7695	4.1881	5.2077	2.1513	2.4962	2.4927	3.0511		3.0396	2.5081	2.5297	3.1336	4.7183	4.3475	6.1711	5.1140	5.4352	3.0512	2.4948	2.5031
H12	2.7867	2.1555	1.0874	2.1618	2.8045	4.2297	2.7495	3.7770	3.1475	2.5928	3.0396		1.7490	3.0527	2.4931	2.5829	3.1349	4.9111	4.7703	4.4257	2.5378	3.1207	3.7406
H13	2.6657	2.1524	1.0870	2.1474	2.7344	4.1764	3.4772	3.6767	2.4519	2.9902	2.5081	1.7490		2.5071	3.0480	3.0392	2.5078	4.8415	4.3971	4.7223	3.7373	3.8386	4.2994
H14	4.1695	2.7940	2.1586	1.0869	2.1569	2.7760	3.4841	4.8648	4.3061	4.7343	2.5297	3.0527	2.5071		1.7498	3.0484	2.4940	3.7707	2.5851	3.1267	4.1140	3.1086	4.3011
H15	4.3026	2.8646	2.1683	1.0846	2.1515	2.7631	2.8536	5.0123	4.7756	4.5362	3.1336	2.4931	3.0480	1.7498		2.4940	3.0440	3.7596	3.1103	2.5725	3.1379	2.2719	3.8450
H16	5.2150	4.2423	2.7756	2.1577	1.0858	2.1611	4.7150	6.2074	5.3476	5.1564	4.7183	2.5829	3.0392	3.0484	2.4940		1.7483	2.5015	3.0621	2.5107	4.6175	4.5159	5.7925
H17	5.1171	4.2030	2.7761	2.1582	1.0857	2.1611	5.1268	6.0997	4.9453	5.3432	4.3475	3.1349	2.5078	2.4940	3.0440	1.7483		2.5010	2.5111	3.0622	5.3352	4.9918	6.1109
H18	7.2453	6.0632	4.7305	3.5010	2.1806	1.0845	6.5308	8.1685	7.2699	7.4113	6.1711	4.9111	4.8415	3.7707	3.7596	2.5015	2.5010		1.7572	1.7571	6.6766	6.0276	7.5479
H19	6.6053	5.2806	4.2372	2.8051	2.1739	1.0850	5.7797	7.3970	6.6438	7.0066	5.1140	4.7703	4.3971	2.5851	3.1103	3.0621	2.5111	1.7572		1.7572	6.1963	5.1815	6.6803
H20	6.6824	5.3128	4.2374	2.8054	2.1741	1.0850	5.4168	7.4872	6.9504	6.8650	5.4352	4.4257	4.7223	3.1267	2.5725	2.5107	3.0622	1.7571	1.7572		5.5878	4.7233	6.3898
H21	2.7781	2.1676	2.7859	3.5186	4.7317	5.7909	1.0858	3.1159	3.7778	2.5855	3.0512	2.5378	3.7373	4.1140	3.1379	4.6175	5.3352	6.6766	6.1963	5.5878		1.7590	1.7580
H22	3.4777	2.1879	2.8308	2.8590	4.2893	5.0082	1.0832	3.7404	4.3283	3.7809	2.4948	3.1207	3.8386	3.1086	2.2719	4.5159	4.9918	6.0276	5.1815	4.7233	1.7590		1.7528
H23	2.7304	2.1735	3.4953	4.1388	5.6077	6.5483	1.0850	2.5124	3.7308	3.0763	2.5031	3.7406	4.2994	4.3011	3.8450	5.7925	6.1109	7.5479	6.6803	6.3898	1.7580	1.7528

picture of 2-methylhexane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	C3	109.886	C1	C2	C7	109.650
C1	C2	H11	108.478	C2	C1	H8	110.898
C2	C1	H9	111.018	C2	C1	H10	110.140
C2	C3	C4	114.352	C2	C3	H12	108.781
C2	C3	H13	108.560	C2	C7	H21	110.004
C2	C7	H22	111.787	C2	C7	H23	110.519
C3	C2	C7	111.738	C3	C2	H11	108.320
C3	C4	C5	112.114	C3	C4	H14	109.231
C3	C4	H15	110.128	C4	C3	H12	109.451
C4	C3	H13	108.355	C4	C5	C6	112.052
C4	C5	H16	109.203	C4	C5	H17	109.247
C5	C4	H14	109.080	C5	C4	H15	108.787
C5	C6	H18	111.115	C5	C6	H19	110.553
C5	C6	H20	110.565	C6	C5	H16	109.486
C6	C5	H17	109.492	C7	C2	H11	108.694
H8	C1	H9	108.229	H8	C1	H10	108.199
H9	C1	H10	108.263	H12	C3	H13	107.096
H14	C4	H15	107.380	H16	C5	H17	107.239
H18	C6	H19	108.182	H18	C6	H20	108.174
H19	C6	H20	108.148	H21	C7	H22	108.384
H21	C7	H23	108.152	H22	C7	H23	107.884

Electronic energy levels

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

Number	Element	Mulliken
1	C	-0.550
2	C	-0.315
3	C	-0.367
4	C	-0.405
5	C	-0.421
6	C	-0.583
7	C	-0.556
8	H	0.196
9	H	0.196
10	H	0.194
11	H	0.212
12	H	0.197
13	H	0.202
14	H	0.200
15	H	0.206
16	H	0.204
17	H	0.203
18	H	0.199
19	H	0.197
20	H	0.197
21	H	0.193
22	H	0.202
23	H	0.197

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	0.015	-0.015	-0.037	0.043
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-49.900	-0.226	0.202
y	-0.226	-49.377	0.219
z	0.202	0.219	-48.746

Traceless
	x	y	z
x	-0.838	-0.226	0.202
y	-0.226	-0.054	0.219
z	0.202	0.219	0.892

Polar
3z²-r²	1.785
x²-y²	-0.523
xy	-0.226
xz	0.202
yz	0.219

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

	x	y	z
x	11.978	0.014	0.021
y	0.014	9.763	0.030
z	0.021	0.030	9.257

<r²> (average value of r²) Å²

<r²>	0.000
(<r²>)^1/2	0.000

All results from a given calculation for C₇H₁₆ (2-methylhexane)

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 C7H16 (2-methylhexane)

using model chemistry: HF/3-21G*

States and conformations

All results from a given calculation for C₇H₁₆ (2-methylhexane)