CCCBDB calculation results Page

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

Energy calculated at HF/CEP-31G*

	hartrees
Energy at 0K	-47.734423
Energy at 298.15K	-47.752050
Nuclear repulsion energy	182.764427

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	3284	2949	113.85
2	A	3279	2945	293.49
3	A	3273	2939	117.75
4	A	3271	2938	124.66
5	A	3270	2937	49.58
6	A	3262	2929	2.14
7	A	3258	2926	21.44
8	A	3236	2906	2.01
9	A	3227	2898	8.34
10	A	3215	2887	23.44
11	A	3210	2883	44.54
12	A	3208	2881	154.93
13	A	3203	2876	47.62
14	A	3202	2875	6.49
15	A	3200	2873	30.13
16	A	3193	2867	17.82
17	A	1640	1473	11.37
18	A	1637	1470	2.56
19	A	1632	1465	2.22
20	A	1628	1462	0.14
21	A	1625	1460	4.89
22	A	1623	1458	1.74
23	A	1619	1454	0.77
24	A	1616	1451	0.49
25	A	1611	1447	0.15
26	A	1563	1404	0.43
27	A	1556	1397	3.65
28	A	1550	1392	3.58
29	A	1546	1388	0.84
30	A	1510	1356	4.04
31	A	1486	1334	2.61
32	A	1452	1303	0.14
33	A	1445	1297	0.56
34	A	1423	1278	0.37
35	A	1379	1238	5.49
36	A	1352	1214	1.56
37	A	1291	1159	2.14
38	A	1286	1155	1.10
39	A	1254	1126	1.08
40	A	1171	1052	1.13
41	A	1140	1023	0.19
42	A	1116	1002	0.33
43	A	1100	988	0.34
44	A	1037	931	0.06
45	A	1024	920	0.26
46	A	996	894	0.74
47	A	973	874	1.35
48	A	963	865	0.72
49	A	877	787	0.37
50	A	828	743	0.11
51	A	764	686	1.94
52	A	506	454	0.15
53	A	458	411	0.01
54	A	431	387	0.04
55	A	322	289	0.03
56	A	315	283	0.01
57	A	271	243	0.00
58	A	257	231	0.00
59	A	244	219	0.00
60	A	151	135	0.00
61	A	135	121	0.00
62	A	90	81	0.01
63	A	61	55	0.00

Unscaled Zero Point Vibrational Energy (zpe) 50871.6 cm^-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 45682.7 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/CEP-31G*

A	B	C
0.20209	0.03285	0.02989

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

Geometric Data calculated at HF/CEP-31G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.824	-0.915	-0.046
C2	-1.646	0.032	-0.352
C3	-0.330	-0.563	0.197
C4	0.950	0.197	-0.203
C5	2.233	-0.515	0.268
C6	3.512	0.246	-0.128
C7	-1.939	1.436	0.213
H8	-3.760	-0.527	-0.454
H9	-2.658	-1.907	-0.473
H10	-2.957	-1.035	1.033
H11	-1.554	0.115	-1.439
H12	-0.392	-0.621	1.288
H13	-0.243	-1.593	-0.161
H14	0.980	0.309	-1.292
H15	0.935	1.207	0.213
H16	2.202	-0.634	1.355
H17	2.265	-1.523	-0.154
H18	4.407	-0.278	0.217
H19	3.584	0.353	-1.213
H20	3.522	1.248	0.307
H21	-2.004	1.409	1.304
H22	-1.166	2.157	-0.058
H23	-2.890	1.816	-0.167

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		1.5420	2.5302	3.9378	5.0823	6.4422	2.5262	1.0921	1.0924	1.0932	2.1484	2.7896	2.6710	4.1863	4.3244	5.2256	5.1262	7.2636	6.6359	6.7145	2.8104	3.4915	2.7348
C2	1.5420		1.5449	2.6058	3.9661	5.1677	1.5422	2.1886	2.1901	2.1847	1.0937	2.1658	2.1553	2.8033	2.8919	4.2626	4.2133	6.0875	5.3104	5.3507	2.1842	2.1991	2.1827
C3	2.5302	1.5449		1.5417	2.5644	3.9400	2.5659	3.4909	2.7702	2.7962	2.1520	1.0946	1.0941	2.1664	2.1756	2.7858	2.7891	4.7456	4.2601	4.2587	2.8139	2.8571	3.5131
C4	3.9378	2.6058	1.5417		1.5409	2.5637	3.1707	4.7718	4.1855	4.2787	2.7931	2.1667	2.1517	1.0945	1.0924	2.1649	2.1654	3.5142	2.8251	2.8254	3.5314	2.8883	4.1673
C5	5.0823	3.9661	2.5644	1.5409		1.5403	4.6054	6.0359	5.1388	5.2708	4.2009	2.8175	2.7343	2.1635	2.1568	1.0934	1.0934	2.1875	2.1848	2.1852	4.7673	4.3358	5.6446
C6	6.4422	5.1677	3.9400	2.5637	1.5403		5.5896	7.3202	6.5442	6.6955	5.2344	4.2422	4.1815	2.7874	2.7715	2.1649	2.1644	1.0920	1.0929	1.0929	5.8167	5.0542	6.5917
C7	2.5262	1.5422	2.5659	3.1707	4.6054	5.5896		2.7603	3.4880	2.7958	2.1503	2.7896	3.4918	3.4721	2.8826	4.7684	5.1537	6.5725	5.8057	5.4649	1.0937	1.0908	1.0924
H8	1.0921	2.1886	3.4909	4.7718	6.0359	7.3202	2.7603		1.7653	1.7647	2.4998	3.7932	3.6863	4.8857	5.0491	6.2315	6.1136	8.1978	7.4353	7.5342	3.1506	3.7541	2.5163
H9	1.0924	2.1901	2.7702	4.1855	5.1388	6.5442	3.4880	1.7653		1.7652	2.4980	3.1450	2.4553	4.3381	4.8038	5.3467	4.9483	7.2831	6.6799	6.9832	3.8188	4.3494	3.7426
H10	1.0932	2.1847	2.7962	4.2787	5.2708	6.6955	2.7958	1.7647	1.7652		3.0658	2.6104	3.0164	4.7653	4.5653	5.1845	5.3767	7.4468	7.0532	6.9078	2.6373	3.8193	3.0941
H11	2.1484	1.0937	2.1520	2.7931	4.2009	5.2344	2.1503	2.4998	2.4980	3.0658		3.0542	2.5035	2.5457	3.1802	4.7406	4.3489	6.1985	5.1482	5.4863	3.0667	2.4960	2.5093
H12	2.7896	2.1658	1.0946	2.1667	2.8175	4.2422	2.7896	3.7932	3.1450	2.6104	3.0542		1.7511	3.0665	2.5017	2.5950	3.1544	4.9284	4.7969	4.4474	2.5929	3.1830	3.7812
H13	2.6710	2.1553	1.0941	2.1517	2.7343	4.1815	3.4918	3.6863	2.4553	3.0164	2.5035	1.7511		2.5285	3.0607	3.0329	2.5089	4.8471	4.4206	4.7406	3.7766	3.8638	4.3159
H14	4.1863	2.8033	2.1664	1.0945	2.1635	2.7874	3.4721	4.8857	4.3381	4.7653	2.5457	3.0665	2.5285		1.7527	3.0638	2.5098	3.7894	2.6053	3.1465	4.1059	3.0898	4.3027
H15	4.3244	2.8919	2.1756	1.0924	2.1568	2.7715	2.8826	5.0491	4.8038	4.5653	3.1802	2.5017	3.0607	1.7527		2.5100	3.0586	3.7757	3.1271	2.5895	3.1419	2.3218	3.8914
H16	5.2256	4.2626	2.7858	2.1649	1.0934	2.1649	4.7684	6.2315	5.3467	5.1845	4.7406	2.5950	3.0329	3.0638	2.5100		1.7525	2.5060	3.0783	2.5268	4.6768	4.5972	5.8522
H17	5.1262	4.2133	2.7891	2.1654	1.0934	2.1644	5.1537	6.1136	4.9483	5.3767	4.3489	3.1544	2.5089	2.5098	3.0586	1.7525		2.5053	2.5259	3.0782	5.3804	5.0323	6.1414
H18	7.2636	6.0875	4.7456	3.5142	2.1875	1.0920	6.5725	8.1978	7.2831	7.4468	6.1985	4.9284	4.8471	3.7894	3.7757	2.5060	2.5053		1.7659	1.7659	6.7175	6.0875	7.6003
H19	6.6359	5.3104	4.2601	2.8251	2.1848	1.0929	5.8057	7.4353	6.6799	7.0532	5.1482	4.7969	4.4206	2.6053	3.1271	3.0783	2.5259	1.7659		1.7650	6.2194	5.2109	6.7189
H20	6.7145	5.3507	4.2587	2.8254	2.1852	1.0929	5.4649	7.5342	6.9832	6.9078	5.4863	4.4474	4.7406	3.1465	2.5895	2.5268	3.0782	1.7659	1.7650		5.6182	4.7896	6.4545
H21	2.8104	2.1842	2.8139	3.5314	4.7673	5.8167	1.0937	3.1506	3.8188	2.6373	3.0667	2.5929	3.7766	4.1059	3.1419	4.6768	5.3804	6.7175	6.2194	5.6182		1.7658	1.7650
H22	3.4915	2.1991	2.8571	2.8883	4.3358	5.0542	1.0908	3.7541	4.3494	3.8193	2.4960	3.1830	3.8638	3.0898	2.3218	4.5972	5.0323	6.0875	5.2109	4.7896	1.7658		1.7605
H23	2.7348	2.1827	3.5131	4.1673	5.6446	6.5917	1.0924	2.5163	3.7426	3.0941	2.5093	3.7812	4.3159	4.3027	3.8914	5.8522	6.1414	7.6003	6.7189	6.4545	1.7650	1.7605

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	110.101	C1	C2	C7	109.981
C1	C2	H11	107.988	C2	C1	H8	111.224
C2	C1	H9	111.327	C2	C1	H10	110.850
C2	C3	C4	115.183	C2	C3	H12	109.088
C2	C3	H13	108.303	C2	C7	H21	110.765
C2	C7	H22	112.137	C2	C7	H23	110.732
C3	C2	C7	112.438	C3	C2	H11	108.070
C3	C4	C5	112.586	C3	C4	H14	109.358
C3	C4	H15	110.198	C4	C3	H12	109.372
C4	C3	H13	108.245	C4	C5	C6	112.615
C4	C5	H16	109.361	C4	C5	H17	109.393
C5	C4	H14	109.187	C5	C4	H15	108.786
C5	C6	H18	111.266	C5	C6	H19	111.002
C5	C6	H20	111.026	C6	C5	H16	109.398
C6	C5	H17	109.361	C7	C2	H11	108.124
H8	C1	H9	107.824	H8	C1	H10	107.710
H9	C1	H10	107.741	H12	C3	H13	106.275
H14	C4	H15	106.538	H16	C5	H17	106.529
H18	C6	H19	107.849	H18	C6	H20	107.842
H19	C6	H20	107.699	H21	C7	H22	107.862
H21	C7	H23	107.678	H22	C7	H23	107.483

Electronic energy levels

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

Number	Element	Mulliken
1	C	-0.343
2	C	0.130
3	C	-0.281
4	C	-0.224
5	C	-0.081
6	C	-0.292
7	C	-0.434
8	H	0.131
9	H	0.113
10	H	0.087
11	H	0.076
12	H	0.080
13	H	0.085
14	H	0.074
15	H	0.074
16	H	0.073
17	H	0.069
18	H	0.136
19	H	0.090
20	H	0.089
21	H	0.095
22	H	0.128
23	H	0.125

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

	x	y	z	Total
	0.025	-0.046	-0.078	0.094
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-50.018	-0.429	0.359
y	-0.429	-48.929	0.380
z	0.359	0.380	-47.533

Traceless
	x	y	z
x	-1.786	-0.429	0.359
y	-0.429	-0.154	0.380
z	0.359	0.380	1.940

Polar
3z²-r²	3.880
x²-y²	-1.088
xy	-0.429
xz	0.359
yz	0.380

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

	x	y	z
x	12.541	0.177	-0.053
y	0.177	10.076	-0.016
z	-0.053	-0.016	9.288

<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/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 C7H16 (2-methylhexane)

using model chemistry: HF/CEP-31G*

States and conformations

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