CCCBDB calculation results Page

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

Energy calculated at CISD/6-31G*

	hartrees
Energy at 0K	-275.198655
Energy at 298.15K	-275.216271
Nuclear repulsion energy	319.826086

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 CISD/6-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3250	3009	38.48
2	A	3241	3000	45.05
3	A	3239	2998	79.61
4	A	3238	2998	53.41
5	A	3235	2995	60.15
6	A	3228	2989	4.06
7	A	3209	2971	55.86
8	A	3186	2949	2.01
9	A	3176	2940	8.39
10	A	3165	2930	9.79
11	A	3164	2929	42.52
12	A	3159	2924	85.31
13	A	3157	2923	11.01
14	A	3149	2916	12.83
15	A	3141	2908	12.33
16	A	3137	2905	5.47
17	A	1617	1497	13.81
18	A	1615	1495	2.16
19	A	1608	1489	2.85
20	A	1604	1485	0.68
21	A	1603	1484	5.63
22	A	1600	1481	2.21
23	A	1595	1477	0.55
24	A	1594	1476	0.95
25	A	1587	1469	0.20
26	A	1528	1415	5.60
27	A	1523	1410	2.77
28	A	1519	1406	1.90
29	A	1514	1402	6.79
30	A	1484	1374	3.21
31	A	1466	1357	1.33
32	A	1430	1324	0.15
33	A	1416	1311	0.32
34	A	1402	1298	0.54
35	A	1360	1259	1.02
36	A	1336	1237	1.13
37	A	1287	1191	0.16
38	A	1274	1179	2.66
39	A	1243	1151	1.17
40	A	1163	1076	1.84
41	A	1142	1057	0.20
42	A	1111	1029	0.26
43	A	1096	1014	0.79
44	A	1030	954	0.22
45	A	1018	942	0.56
46	A	985	912	1.25
47	A	973	901	1.89
48	A	960	888	1.13
49	A	876	811	0.64
50	A	833	772	0.15
51	A	771	714	2.59
52	A	505	468	0.24
53	A	461	427	0.04
54	A	433	401	0.06
55	A	323	299	0.01
56	A	316	293	0.02
57	A	271	251	0.00
58	A	258	239	0.00
59	A	242	224	0.01
60	A	152	141	0.00
61	A	133	124	0.01
62	A	90	83	0.01
63	A	61	57	0.00

Unscaled Zero Point Vibrational Energy (zpe) 50239.3 cm^-1
Scaled (by 0.9258) Zero Point Vibrational Energy (zpe) 46511.6 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 CISD/6-31G*

A	B	C
0.20551	0.03355	0.03049

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

Geometric Data calculated at CISD/6-31G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.806	-0.896	-0.037
C2	-1.633	0.030	-0.346
C3	-0.329	-0.569	0.185
C4	0.936	0.195	-0.191
C5	2.210	-0.519	0.248
C6	3.475	0.246	-0.117
C7	-1.900	1.428	0.206
H8	-3.736	-0.505	-0.447
H9	-2.648	-1.889	-0.455
H10	-2.938	-1.005	1.040
H11	-1.544	0.108	-1.433
H12	-0.393	-0.649	1.273
H13	-0.242	-1.591	-0.189
H14	0.962	0.342	-1.274
H15	0.920	1.191	0.252
H16	2.179	-0.677	1.328
H17	2.241	-1.511	-0.203
H18	4.368	-0.285	0.207
H19	3.547	0.391	-1.194
H20	3.486	1.230	0.350
H21	-1.948	1.407	1.295
H22	-1.126	2.136	-0.081
H23	-2.850	1.813	-0.160

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		1.5263	2.5085	3.9012	5.0381	6.3847	2.5061	1.0889	1.0889	1.0901	2.1325	2.7565	2.6611	4.1549	4.2811	5.1728	5.0870	7.2045	6.5843	6.6526	2.7960	3.4667	2.7123
C2	1.5263		1.5297	2.5789	3.9267	5.1175	1.5262	2.1727	2.1737	2.1666	1.0932	2.1490	2.1418	2.7737	2.8679	4.2222	4.1715	6.0347	5.2608	5.3031	2.1655	2.1823	2.1668
C3	2.5085	1.5297		1.5249	2.5400	3.9021	2.5402	3.4658	2.7440	2.7798	2.1333	1.0933	1.0921	2.1503	2.1594	2.7579	2.7647	4.7059	4.2241	4.2207	2.7852	2.8322	3.4852
C4	3.9012	2.5789	1.5249		1.5247	2.5405	3.1175	4.7314	4.1543	4.2383	2.7752	2.1507	2.1397	1.0926	1.0904	2.1473	2.1481	3.4882	2.8034	2.8043	3.4635	2.8341	4.1174
C5	5.0381	3.9267	2.5400	1.5247		1.5232	4.5472	5.9864	5.0958	5.2307	4.1607	2.8008	2.7114	2.1477	2.1416	1.0913	1.0912	2.1716	2.1671	2.1673	4.6999	4.2759	5.5860
C6	6.3847	5.1175	3.9021	2.5405	1.5232		5.5124	7.2577	6.4933	6.6355	5.1908	4.2072	4.1469	2.7676	2.7486	2.1495	2.1496	1.0884	1.0891	1.0891	5.7226	4.9742	6.5162
C7	2.5061	1.5262	2.5402	3.1175	4.5472	5.5124		2.7452	3.4638	2.7734	2.1338	2.7785	3.4666	3.4001	2.8303	4.7242	5.0941	6.4975	5.7181	5.3907	1.0905	1.0874	1.0889
H8	1.0889	2.1727	3.4658	4.7314	5.9864	7.2577	2.7452		1.7605	1.7599	2.4801	3.7621	3.6681	4.8453	5.0050	6.1776	6.0659	8.1337	7.3756	7.4700	3.1453	3.7314	2.4985
H9	1.0889	2.1737	2.7440	4.1543	5.0958	6.4933	3.4638	1.7605		1.7604	2.4822	3.0994	2.4388	4.3221	4.7666	5.2860	4.9095	7.2275	6.6420	6.9279	3.7974	4.3194	3.7194
H10	1.0901	2.1666	2.7798	4.2383	5.2307	6.6355	2.7734	1.7599	1.7604		3.0484	2.5797	3.0200	4.7305	4.5091	5.1351	5.3497	7.3886	6.9991	6.8362	2.6203	3.7954	3.0643
H11	2.1325	1.0932	2.1333	2.7752	4.1607	5.1908	2.1338	2.4801	2.4822	3.0484		3.0363	2.4760	2.5227	3.1759	4.7006	4.2966	6.1483	5.1044	5.4532	3.0484	2.4730	2.4961
H12	2.7565	2.1490	1.0933	2.1507	2.8008	4.2072	2.7785	3.7621	3.0994	2.5797	3.0363		1.7459	3.0508	2.4813	2.5728	3.1407	4.8933	4.7640	4.4082	2.5776	3.1823	3.7618
H13	2.6611	2.1418	1.0921	2.1397	2.7114	4.1469	3.4666	3.6681	2.4388	3.0200	2.4760	1.7459		2.5226	3.0475	2.9992	2.4840	4.8080	4.3924	4.7058	3.7553	3.8321	4.2885
H14	4.1549	2.7737	2.1503	1.0926	2.1477	2.7676	3.4001	4.8453	4.3221	4.7305	2.5227	3.0508	2.5226		1.7466	3.0469	2.4928	3.7661	2.5858	3.1291	4.0254	3.0008	4.2354
H15	4.2811	2.8679	2.1594	1.0904	2.1416	2.7486	2.8303	5.0050	4.7666	4.5091	3.1759	2.4813	3.0475	1.7466		2.4959	3.0423	3.7507	3.1029	2.5673	3.0596	2.2785	3.8434
H16	5.1728	4.2222	2.7579	2.1473	1.0913	2.1495	4.7242	6.1776	5.2860	5.1351	4.7006	2.5728	2.9992	3.0469	2.4959		1.7452	2.4909	3.0613	2.5102	4.6226	4.5624	5.8050
H17	5.0870	4.1715	2.7647	2.1481	1.0912	2.1496	5.0941	6.0659	4.9095	5.3497	4.2966	3.1407	2.4840	2.4928	3.0423	1.7452		2.4899	2.5113	3.0615	5.3205	4.9654	6.0802
H18	7.2045	6.0347	4.7059	3.4882	2.1716	1.0884	6.4975	8.1337	7.2275	7.3886	6.1483	4.8933	4.8080	3.7661	3.7507	2.4909	2.4899		1.7592	1.7591	6.6285	6.0108	7.5257
H19	6.5843	5.2608	4.2241	2.8034	2.1671	1.0891	5.7181	7.3756	6.6420	6.9991	5.1044	4.7640	4.3924	2.5858	3.1029	3.0613	2.5113	1.7592		1.7584	6.1169	5.1106	6.6337
H20	6.6526	5.3031	4.2207	2.8043	2.1673	1.0891	5.3907	7.4700	6.9279	6.8362	5.4532	4.4082	4.7058	3.1291	2.5673	2.5102	3.0615	1.7591	1.7584		5.5177	4.7194	6.3826
H21	2.7960	2.1655	2.7852	3.4635	4.6999	5.7226	1.0905	3.1453	3.7974	2.6203	3.0484	2.5776	3.7553	4.0254	3.0596	4.6226	5.3205	6.6285	6.1169	5.5177		1.7606	1.7600
H22	3.4667	2.1823	2.8322	2.8341	4.2759	4.9742	1.0874	3.7314	4.3194	3.7954	2.4730	3.1823	3.8321	3.0008	2.2785	4.5624	4.9654	6.0108	5.1106	4.7194	1.7606		1.7556
H23	2.7123	2.1668	3.4852	4.1174	5.5860	6.5162	1.0889	2.4985	3.7194	3.0643	2.4961	3.7618	4.2885	4.2354	3.8434	5.8050	6.0802	7.5257	6.6337	6.3826	1.7600	1.7556

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	110.341	C1	C2	C7	110.372
C1	C2	H11	107.852	C2	C1	H8	111.262
C2	C1	H9	111.338	C2	C1	H10	110.696
C2	C3	C4	115.189	C2	C3	H12	108.895
C2	C3	H13	108.402	C2	C7	H21	110.594
C2	C7	H22	112.135	C2	C7	H23	110.793
C3	C2	C7	112.455	C3	C2	H11	107.689
C3	C4	C5	112.793	C3	C4	H14	109.361
C3	C4	H15	110.206	C4	C3	H12	109.351
C4	C3	H13	108.563	C4	C5	C6	112.923
C4	C5	H16	109.213	C4	C5	H17	109.288
C5	C4	H14	109.170	C5	C4	H15	108.821
C5	C6	H18	111.424	C5	C6	H19	111.018
C5	C6	H20	111.038	C6	C5	H16	109.492
C6	C5	H17	109.510	C7	C2	H11	107.959
H8	C1	H9	107.873	H8	C1	H10	107.735
H9	C1	H10	107.778	H12	C3	H13	106.048
H14	C4	H15	106.275	H16	C5	H17	106.191
H18	C6	H19	107.772	H18	C6	H20	107.767
H19	C6	H20	107.653	H21	C7	H22	107.878
H21	C7	H23	107.719	H22	C7	H23	107.546

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: CISD/6-31G*

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: CISD/6-31G*

States and conformations

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