CCCBDB calculation results Page

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

Energy calculated at MP2/6-31+G**

	hartrees
Energy at 0K	-275.464764
Energy at 298.15K	-275.482152
Nuclear repulsion energy	319.540380

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 MP2/6-31+G**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3210	3019	31.51
2	A	3205	3014	36.76
3	A	3202	3012	51.23
4	A	3199	3009	35.93
5	A	3192	3003	64.23
6	A	3188	2999	5.18
7	A	3165	2977	56.28
8	A	3145	2958	3.87
9	A	3128	2943	12.34
10	A	3109	2925	34.21
11	A	3104	2919	60.30
12	A	3102	2918	27.10
13	A	3099	2915	31.29
14	A	3091	2907	26.80
15	A	3086	2902	9.06
16	A	3075	2892	12.11
17	A	1553	1461	18.27
18	A	1551	1459	2.39
19	A	1546	1454	3.93
20	A	1543	1452	7.22
21	A	1540	1449	1.26
22	A	1536	1445	3.18
23	A	1531	1440	0.34
24	A	1531	1440	0.69
25	A	1519	1429	0.22
26	A	1458	1371	5.52
27	A	1453	1367	5.18
28	A	1440	1355	7.77
29	A	1437	1352	0.75
30	A	1411	1327	3.35
31	A	1398	1315	1.68
32	A	1364	1283	0.26
33	A	1354	1273	0.70
34	A	1341	1261	0.43
35	A	1298	1221	0.54
36	A	1281	1205	1.01
37	A	1235	1162	0.10
38	A	1225	1152	1.84
39	A	1200	1128	1.09
40	A	1123	1056	1.49
41	A	1114	1048	0.21
42	A	1078	1014	0.29
43	A	1055	992	0.40
44	A	997	938	0.18
45	A	986	927	0.51
46	A	948	892	0.99
47	A	937	881	1.76
48	A	927	872	0.63
49	A	851	800	0.42
50	A	807	759	0.16
51	A	748	704	1.71
52	A	487	458	0.22
53	A	446	420	0.02
54	A	417	392	0.07
55	A	312	294	0.03
56	A	304	286	0.02
57	A	263	248	0.00
58	A	250	235	0.00
59	A	231	217	0.01
60	A	146	138	0.01
61	A	125	118	0.01
62	A	86	81	0.01
63	A	59	56	0.00

Unscaled Zero Point Vibrational Energy (zpe) 48872.1 cm^-1
Scaled (by 0.9406) Zero Point Vibrational Energy (zpe) 45969.1 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 MP2/6-31+G**

A	B	C
0.20525	0.03355	0.03047

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

Geometric Data calculated at MP2/6-31+G**

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.816	-0.886	-0.029
C2	-1.635	0.029	-0.350
C3	-0.332	-0.578	0.179
C4	0.934	0.195	-0.182
C5	2.212	-0.529	0.237
C6	3.475	0.252	-0.111
C7	-1.885	1.431	0.203
H8	-3.746	-0.488	-0.438
H9	-2.664	-1.886	-0.441
H10	-2.938	-0.982	1.052
H11	-1.548	0.102	-1.442
H12	-0.404	-0.667	1.270
H13	-0.242	-1.598	-0.210
H14	0.957	0.364	-1.265
H15	0.920	1.182	0.289
H16	2.179	-0.714	1.315
H17	2.241	-1.510	-0.246
H18	4.374	-0.285	0.195
H19	3.538	0.426	-1.187
H20	3.479	1.223	0.385
H21	-1.915	1.406	1.295
H22	-1.108	2.134	-0.097
H23	-2.841	1.820	-0.150

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		1.5279	2.5114	3.9061	5.0473	6.3939	2.5082	1.0913	1.0912	1.0928	2.1396	2.7487	2.6769	4.1621	4.2819	5.1759	5.1001	7.2184	6.5904	6.6521	2.7966	3.4706	2.7096
C2	1.5279		1.5314	2.5805	3.9313	5.1210	1.5278	2.1752	2.1751	2.1650	1.0971	2.1510	2.1465	2.7690	2.8752	4.2280	4.1722	6.0420	5.2554	5.3033	2.1642	2.1853	2.1689
C3	2.5114	1.5314		1.5269	2.5451	3.9077	2.5383	3.4704	2.7446	2.7779	2.1367	1.0972	1.0957	2.1523	2.1621	2.7601	2.7702	4.7153	4.2249	4.2205	2.7722	2.8341	3.4858
C4	3.9061	2.5805	1.5269		1.5268	2.5425	3.1020	4.7373	4.1647	4.2315	2.7854	2.1545	2.1442	1.0961	1.0936	2.1487	2.1493	3.4931	2.8001	2.8027	3.4306	2.8181	4.1106
C5	5.0473	3.9313	2.5451	1.5268		1.5258	4.5411	5.9962	5.1062	5.2334	4.1656	2.8152	2.7131	2.1513	2.1444	1.0941	1.0940	2.1764	2.1675	2.1679	4.6790	4.2694	5.5856
C6	6.3939	5.1210	3.9077	2.5425	1.5258		5.4970	7.2668	6.5092	6.6338	5.1989	4.2188	4.1529	2.7724	2.7487	2.1554	2.1554	1.0904	1.0912	1.0911	5.6891	4.9552	6.5083
C7	2.5082	1.5278	2.5383	3.1020	4.5411	5.4970		2.7494	3.4671	2.7669	2.1410	2.7808	3.4702	3.3712	2.8168	4.7277	5.0866	6.4893	5.6871	5.3707	1.0933	1.0897	1.0913
H8	1.0913	2.1752	3.4704	4.7373	5.9962	7.2668	2.7494		1.7674	1.7656	2.4875	3.7579	3.6832	4.8508	5.0090	6.1836	6.0773	8.1474	7.3796	7.4708	3.1534	3.7353	2.4963
H9	1.0912	2.1751	2.7446	4.1647	5.1062	6.5092	3.4671	1.7674		1.7666	2.4890	3.0860	2.4505	4.3417	4.7735	5.2837	4.9237	7.2457	6.6607	6.9345	3.7960	4.3241	3.7215
H10	1.0928	2.1650	2.7779	4.2315	5.2334	6.6338	2.7669	1.7656	1.7666		3.0539	2.5632	3.0402	4.7278	4.4889	5.1311	5.3655	7.3950	6.9953	6.8184	2.6095	3.7926	3.0514
H11	2.1396	1.0971	2.1367	2.7854	4.1656	5.1989	2.1410	2.4875	2.4890	3.0539		3.0420	2.4722	2.5249	3.2020	4.7073	4.2882	6.1562	5.1029	5.4652	3.0539	2.4763	2.5086
H12	2.7487	2.1510	1.0972	2.1545	2.8152	4.2188	2.7808	3.7579	3.0860	2.5632	3.0420		1.7560	3.0560	2.4763	2.5838	3.1630	4.9119	4.7713	4.4082	2.5654	3.1958	3.7609
H13	2.6769	2.1465	1.0957	2.1442	2.7131	4.1529	3.4702	3.6832	2.4505	3.0402	2.4722	1.7560		2.5293	3.0535	2.9948	2.4847	4.8157	4.3971	4.7072	3.7535	3.8331	4.2946
H14	4.1621	2.7690	2.1523	1.0961	2.1513	2.7724	3.3712	4.8508	4.3417	4.7278	2.5249	3.0560	2.5293		1.7562	3.0516	2.4903	3.7720	2.5831	3.1341	3.9859	2.9600	4.2174
H15	4.2819	2.8752	2.1621	1.0936	2.1444	2.7487	2.8168	5.0090	4.7735	4.4889	3.2020	2.4763	3.0535	1.7562		2.4964	3.0462	3.7537	3.0988	2.5613	3.0166	2.2738	3.8398
H16	5.1759	4.2280	2.7601	2.1487	1.0941	2.1554	4.7277	6.1836	5.2837	5.1311	4.7073	2.5838	2.9948	3.0516	2.4964		1.7534	2.5009	3.0664	2.5114	4.6105	4.5733	5.8113
H17	5.1001	4.1722	2.7702	2.1493	1.0940	2.1554	5.0866	6.0773	4.9237	5.3655	4.2882	3.1630	2.4847	2.4903	3.0462	1.7534		2.4988	2.5131	3.0665	5.3060	4.9523	6.0771
H18	7.2184	6.0420	4.7153	3.4931	2.1764	1.0904	6.4893	8.1474	7.2457	7.3950	6.1562	4.9119	4.8157	3.7720	3.7537	2.5009	2.4988		1.7642	1.7641	6.6045	5.9994	7.5236
H19	6.5904	5.2554	4.2249	2.8001	2.1675	1.0912	5.6871	7.3796	6.6607	6.9953	5.1029	4.7713	4.3971	2.5831	3.0988	3.0664	2.5131	1.7642		1.7633	6.0708	5.0688	6.6113
H20	6.6521	5.3033	4.2205	2.8027	2.1679	1.0911	5.3707	7.4708	6.9345	6.8184	5.4652	4.4082	4.7072	3.1341	2.5613	2.5114	3.0665	1.7641	1.7633		5.4734	4.7017	6.3707
H21	2.7966	2.1642	2.7722	3.4306	4.6790	5.6891	1.0933	3.1534	3.7960	2.6095	3.0539	2.5654	3.7535	3.9859	3.0166	4.6105	5.3060	6.6045	6.0708	5.4734		1.7667	1.7660
H22	3.4706	2.1853	2.8341	2.8181	4.2694	4.9552	1.0897	3.7353	4.3241	3.7926	2.4763	3.1958	3.8331	2.9600	2.2738	4.5733	4.9523	5.9994	5.0688	4.7017	1.7667		1.7616
H23	2.7096	2.1689	3.4858	4.1106	5.5856	6.5083	1.0913	2.4963	3.7215	3.0514	2.5086	3.7609	4.2946	4.2174	3.8398	5.8113	6.0771	7.5236	6.6113	6.3707	1.7660	1.7616

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	110.351	C1	C2	C7	110.333
C1	C2	H11	108.070	C2	C1	H8	111.204
C2	C1	H9	111.198	C2	C1	H10	110.306
C2	C3	C4	115.087	C2	C3	H12	108.707
C2	C3	H13	108.440	C2	C7	H21	110.208
C2	C7	H22	112.117	C2	C7	H23	110.699
C3	C2	C7	112.143	C3	C2	H11	107.613
C3	C4	C5	112.910	C3	C4	H14	109.177
C3	C4	H15	110.095	C4	C3	H12	109.285
C4	C3	H13	108.568	C4	C5	C6	112.798
C4	C5	H16	109.016	C4	C5	H17	109.071
C5	C4	H14	109.108	C5	C4	H15	108.709
C5	C6	H18	111.504	C5	C6	H19	110.748
C5	C6	H20	110.780	C6	C5	H16	109.616
C6	C5	H17	109.621	C7	C2	H11	108.184
H8	C1	H9	108.149	H8	C1	H10	107.883
H9	C1	H10	107.972	H12	C3	H13	106.406
H14	C4	H15	106.644	H16	C5	H17	106.520
H18	C6	H19	107.932	H18	C6	H20	107.927
H19	C6	H20	107.805	H21	C7	H22	108.052
H21	C7	H23	107.873	H22	C7	H23	107.743

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP2/6-31+G**

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: MP2/6-31+G**

States and conformations

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