CCCBDB calculation results Page

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

Energy calculated at MP2/6-31G(2df,p)

	hartrees
Energy at 0K	-275.601227
Energy at 298.15K	-275.618590
Nuclear repulsion energy	319.768946

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 MP2/6-31G(2df,p)

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3197	3020	21.22
2	A	3195	3018	23.86
3	A	3194	3017	32.51
4	A	3188	3011	25.21
5	A	3184	3008	38.87
6	A	3180	3004	3.18
7	A	3158	2982	38.39
8	A	3138	2964	3.09
9	A	3122	2949	8.06
10	A	3101	2929	30.60
11	A	3097	2926	33.03
12	A	3094	2923	14.71
13	A	3091	2920	20.84
14	A	3086	2915	16.51
15	A	3082	2911	1.82
16	A	3070	2900	7.89
17	A	1541	1456	13.02
18	A	1539	1454	2.41
19	A	1533	1448	3.20
20	A	1531	1446	5.80
21	A	1527	1442	1.00
22	A	1523	1438	1.85
23	A	1517	1433	0.63
24	A	1514	1430	0.31
25	A	1503	1419	0.15
26	A	1437	1357	4.61
27	A	1431	1352	3.06
28	A	1419	1341	7.47
29	A	1413	1335	0.23
30	A	1393	1316	4.42
31	A	1383	1306	1.47
32	A	1350	1275	0.32
33	A	1346	1271	0.18
34	A	1331	1257	0.53
35	A	1283	1212	0.96
36	A	1266	1196	1.61
37	A	1218	1151	0.45
38	A	1215	1148	2.14
39	A	1188	1122	1.40
40	A	1112	1050	1.90
41	A	1106	1044	0.18
42	A	1070	1011	0.48
43	A	1046	988	0.76
44	A	988	933	0.46
45	A	977	923	1.18
46	A	936	884	1.65
47	A	926	874	3.38
48	A	917	866	0.23
49	A	847	800	0.75
50	A	796	752	0.29
51	A	744	703	3.40
52	A	477	451	0.30
53	A	438	414	0.08
54	A	409	386	0.07
55	A	310	293	0.01
56	A	299	283	0.04
57	A	267	252	0.00
58	A	254	239	0.00
59	A	238	225	0.01
60	A	149	141	0.00
61	A	125	118	0.02
62	A	87	82	0.01
63	A	63	59	0.00

Unscaled Zero Point Vibrational Energy (zpe) 48580.8 cm^-1
Scaled (by 0.9445) Zero Point Vibrational Energy (zpe) 45884.6 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 MP2/6-31G(2df,p)

A	B	C
0.20512	0.03369	0.03059

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

Geometric Data calculated at MP2/6-31G(2df,p)

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.813	-0.881	-0.027
C2	-1.632	0.030	-0.355
C3	-0.333	-0.582	0.173
C4	0.932	0.193	-0.188
C5	2.205	-0.531	0.241
C6	3.468	0.252	-0.109
C7	-1.874	1.430	0.207
H8	-3.747	-0.483	-0.430
H9	-2.669	-1.884	-0.436
H10	-2.932	-0.976	1.056
H11	-1.549	0.106	-1.447
H12	-0.404	-0.675	1.264
H13	-0.243	-1.603	-0.216
H14	0.959	0.361	-1.271
H15	0.914	1.183	0.278
H16	2.170	-0.711	1.321
H17	2.237	-1.517	-0.234
H18	4.369	-0.278	0.202
H19	3.534	0.420	-1.186
H20	3.468	1.228	0.379
H21	-1.903	1.400	1.300
H22	-1.095	2.133	-0.090
H23	-2.830	1.828	-0.141

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		1.5277	2.5067	3.8996	5.0382	6.3831	2.5053	1.0921	1.0921	1.0934	2.1423	2.7414	2.6766	4.1621	4.2720	5.1653	5.0949	7.2118	6.5827	6.6390	2.7914	3.4701	2.7121
C2	1.5277		1.5302	2.5744	3.9238	5.1106	1.5276	2.1774	2.1777	2.1663	1.0970	2.1513	2.1482	2.7680	2.8661	4.2206	4.1689	6.0352	5.2473	5.2906	2.1657	2.1865	2.1714
C3	2.5067	1.5302		1.5265	2.5396	3.9011	2.5342	3.4684	2.7426	2.7729	2.1389	1.0973	1.0962	2.1549	2.1634	2.7564	2.7651	4.7121	4.2198	4.2152	2.7681	2.8315	3.4844
C4	3.8996	2.5744	1.5265		1.5268	2.5380	3.0915	4.7334	4.1639	4.2238	2.7829	2.1556	2.1461	1.0964	1.0942	2.1510	2.1519	3.4918	2.7967	2.7978	3.4215	2.8067	4.1017
C5	5.0382	3.9238	2.5396	1.5268		1.5261	4.5263	5.9902	5.1034	5.2202	4.1652	2.8063	2.7112	2.1534	2.1464	1.0947	1.0945	2.1791	2.1699	2.1701	4.6615	4.2539	5.5735
C6	6.3831	5.1106	3.9011	2.5380	1.5261		5.4795	7.2591	6.5056	6.6195	5.1939	4.2112	4.1495	2.7671	2.7458	2.1574	2.1577	1.0912	1.0920	1.0920	5.6704	4.9353	6.4920
C7	2.5053	1.5276	2.5342	3.0915	4.5263	5.4795		2.7515	3.4671	2.7615	2.1428	2.7763	3.4690	3.3695	2.8001	4.7092	5.0773	6.4730	5.6756	5.3492	1.0938	1.0907	1.0922
H8	1.0921	2.1774	3.4684	4.7334	5.9902	7.2591	2.7515		1.7675	1.7655	2.4922	3.7528	3.6848	4.8543	5.0003	6.1747	6.0761	8.1435	7.3759	7.4595	3.1524	3.7405	2.5035
H9	1.0921	2.1777	2.7426	4.1639	5.1034	6.5056	3.4671	1.7675		1.7659	2.4967	3.0791	2.4520	4.3470	4.7698	5.2796	4.9240	7.2470	6.6595	6.9290	3.7919	4.3275	3.7271
H10	1.0934	2.1663	2.7729	4.2238	5.2202	6.6195	2.7615	1.7655	1.7659		3.0570	2.5541	3.0397	4.7266	4.4785	5.1154	5.3549	7.3838	6.9847	6.8028	2.6002	3.7881	3.0507
H11	2.1423	1.0970	2.1389	2.7829	4.1652	5.1939	2.1428	2.4922	2.4967	3.0570		3.0445	2.4778	2.5269	3.1939	4.7068	4.2941	6.1557	5.0996	5.4558	3.0566	2.4811	2.5126
H12	2.7414	2.1513	1.0973	2.1556	2.8063	4.2112	2.7763	3.7528	3.0791	2.5541	3.0445		1.7543	3.0592	2.4822	2.5748	3.1511	4.9060	4.7658	4.4045	2.5599	3.1923	3.7581
H13	2.6766	2.1482	1.0962	2.1461	2.7112	4.1495	3.4690	3.6848	2.4520	3.0397	2.4778	1.7543		2.5327	3.0566	2.9963	2.4818	4.8168	4.3932	4.7054	3.7509	3.8333	4.2976
H14	4.1621	2.7680	2.1549	1.0964	2.1534	2.7671	3.3695	4.8543	4.3470	4.7266	2.5269	3.0592	2.5327		1.7545	3.0549	2.4972	3.7699	2.5775	3.1261	3.9853	2.9586	4.2173
H15	4.2720	2.8661	2.1634	1.0942	2.1464	2.7458	2.8001	5.0003	4.7698	4.4785	3.1939	2.4822	3.0566	1.7545		2.5002	3.0498	3.7524	3.0971	2.5567	3.0048	2.2522	3.8220
H16	5.1653	4.2206	2.7564	2.1510	1.0947	2.1574	4.7092	6.1747	5.2796	5.1154	4.7068	2.5748	2.9963	3.0549	2.5002		1.7521	2.5048	3.0697	2.5163	4.5877	4.5532	5.7948
H17	5.0949	4.1689	2.7651	2.1519	1.0945	2.1577	5.0773	6.0761	4.9240	5.3549	4.2941	3.1511	2.4818	2.4972	3.0498	1.7521		2.5038	2.5179	3.0700	5.2918	4.9438	6.0723
H18	7.2118	6.0352	4.7121	3.4918	2.1791	1.0912	6.4730	8.1435	7.2470	7.3838	6.1557	4.9060	4.8168	3.7699	3.7524	2.5048	2.5038		1.7644	1.7644	6.5854	5.9796	7.5089
H19	6.5827	5.2473	4.2198	2.7967	2.1699	1.0920	5.6756	7.3759	6.6595	6.9847	5.0996	4.7658	4.3932	2.5775	3.0971	3.0697	2.5179	1.7644		1.7627	6.0587	5.0562	6.6014
H20	6.6390	5.2906	4.2152	2.7978	2.1701	1.0920	5.3492	7.4595	6.9290	6.8028	5.4558	4.4045	4.7054	3.1261	2.5567	2.5163	3.0700	1.7644	1.7627		5.4527	4.6755	6.3479
H21	2.7914	2.1657	2.7681	3.4215	4.6615	5.6704	1.0938	3.1524	3.7919	2.6002	3.0566	2.5599	3.7509	3.9853	3.0048	4.5877	5.2918	6.5854	6.0587	5.4527		1.7666	1.7656
H22	3.4701	2.1865	2.8315	2.8067	4.2539	4.9353	1.0907	3.7405	4.3275	3.7881	2.4811	3.1923	3.8333	2.9586	2.2522	4.5532	4.9438	5.9796	5.0562	4.6755	1.7666		1.7621
H23	2.7121	2.1714	3.4844	4.1017	5.5735	6.4920	1.0922	2.5035	3.7271	3.0507	2.5126	3.7581	4.2976	4.2173	3.8220	5.7948	6.0723	7.5089	6.6014	6.3479	1.7656	1.7621

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	110.115	C1	C2	C7	110.165
C1	C2	H11	108.295	C2	C1	H8	111.344
C2	C1	H9	111.369	C2	C1	H10	110.379
C2	C3	C4	114.753	C2	C3	H12	108.804
C2	C3	H13	108.626	C2	C7	H21	110.310
C2	C7	H22	112.173	C2	C7	H23	110.862
C3	C2	C7	111.940	C3	C2	H11	107.870
C3	C4	C5	112.558	C3	C4	H14	109.393
C3	C4	H15	110.191	C4	C3	H12	109.390
C4	C3	H13	108.716	C4	C5	C6	112.470
C4	C5	H16	109.162	C4	C5	H17	109.242
C5	C4	H14	109.247	C5	C4	H15	108.829
C5	C6	H18	111.645	C5	C6	H19	110.860
C5	C6	H20	110.878	C6	C5	H16	109.712
C6	C5	H17	109.740	C7	C2	H11	108.343
H8	C1	H9	108.035	H8	C1	H10	107.765
H9	C1	H10	107.798	H12	C3	H13	106.209
H14	C4	H15	106.432	H16	C5	H17	106.324
H18	C6	H19	107.835	H18	C6	H20	107.830
H19	C6	H20	107.628	H21	C7	H22	107.935
H21	C7	H23	107.736	H22	C7	H23	107.658

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP2/6-31G(2df,p)

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: MP2/6-31G(2df,p)

States and conformations

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