CCCBDB calculation results Page

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

Energy calculated at MP2/CEP-31G*

	hartrees
Energy at 0K	-48.605197
Energy at 298.15K	-48.622456
HF Energy	-47.732222
Nuclear repulsion energy	182.176268

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/CEP-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3179	3018	55.28
2	A	3178	3017	75.05
3	A	3175	3014	45.28
4	A	3170	3010	40.12
5	A	3168	3008	88.43
6	A	3163	3003	5.69
7	A	3153	2994	50.97
8	A	3134	2976	6.22
9	A	3119	2961	11.16
10	A	3088	2932	30.85
11	A	3084	2928	41.55
12	A	3078	2922	52.19
13	A	3074	2919	17.72
14	A	3071	2916	19.87
15	A	3068	2912	38.38
16	A	3059	2904	19.03
17	A	1540	1463	17.25
18	A	1533	1455	7.21
19	A	1531	1453	3.48
20	A	1529	1452	7.89
21	A	1524	1447	1.74
22	A	1522	1445	1.70
23	A	1517	1440	0.57
24	A	1514	1438	0.42
25	A	1506	1430	0.25
26	A	1449	1376	8.15
27	A	1446	1373	3.30
28	A	1441	1368	4.43
29	A	1438	1365	7.50
30	A	1409	1338	3.04
31	A	1390	1320	0.54
32	A	1361	1292	0.59
33	A	1356	1287	0.01
34	A	1340	1272	0.59
35	A	1282	1217	0.18
36	A	1272	1208	2.09
37	A	1223	1161	3.51
38	A	1219	1157	0.26
39	A	1193	1133	1.41
40	A	1116	1059	2.66
41	A	1108	1052	0.19
42	A	1075	1021	0.47
43	A	1055	1002	1.63
44	A	993	943	0.50
45	A	983	933	1.16
46	A	944	896	2.11
47	A	931	884	3.77
48	A	919	873	1.35
49	A	845	803	0.91
50	A	797	756	0.39
51	A	733	696	5.24
52	A	479	455	0.26
53	A	439	417	0.04
54	A	409	389	0.05
55	A	310	294	0.02
56	A	299	284	0.03
57	A	258	245	0.01
58	A	241	229	0.00
59	A	231	220	0.01
60	A	149	141	0.00
61	A	124	118	0.01
62	A	85	80	0.01
63	A	59	56	0.00

Unscaled Zero Point Vibrational Energy (zpe) 48538.0 cm^-1
Scaled (by 0.9494) Zero Point Vibrational Energy (zpe) 46082.0 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/CEP-31G*

A	B	C
0.20049	0.03297	0.02993

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

Geometric Data calculated at MP2/CEP-31G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.840	-0.896	-0.030
C2	-1.648	0.029	-0.359
C3	-0.336	-0.584	0.182
C4	0.942	0.204	-0.177
C5	2.230	-0.541	0.238
C6	3.507	0.255	-0.115
C7	-1.901	1.445	0.206
H8	-3.783	-0.494	-0.444
H9	-2.686	-1.909	-0.447
H10	-2.962	-0.993	1.065
H11	-1.557	0.105	-1.461
H12	-0.410	-0.679	1.285
H13	-0.237	-1.613	-0.220
H14	0.963	0.389	-1.270
H15	0.930	1.194	0.317
H16	2.199	-0.736	1.328
H17	2.254	-1.527	-0.264
H18	4.418	-0.291	0.189
H19	3.563	0.438	-1.203
H20	3.508	1.236	0.395
H21	-1.927	1.419	1.312
H22	-1.118	2.157	-0.105
H23	-2.873	1.836	-0.149

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		1.5446	2.5327	3.9422	5.0896	6.4511	2.5334	1.1055	1.1055	1.1063	2.1672	2.7717	2.7073	4.2023	4.3248	5.2219	5.1390	7.2871	6.6452	6.7106	2.8281	3.5070	2.7355
C2	1.5446		1.5459	2.6026	3.9644	5.1654	1.5450	2.1998	2.1999	2.1903	1.1087	2.1762	2.1697	2.7893	2.9083	4.2697	4.2023	6.0993	5.2947	5.3489	2.1912	2.2082	2.1933
C3	2.5327	1.5459		1.5440	2.5666	3.9443	2.5627	3.5047	2.7700	2.8004	2.1601	1.1097	1.1092	2.1784	2.1868	2.7862	2.7925	4.7632	4.2621	4.2585	2.7963	2.8652	3.5218
C4	3.9422	2.6026	1.5440		1.5440	2.5656	3.1262	4.7841	4.2071	4.2682	2.8116	2.1791	2.1662	1.1091	1.1067	2.1741	2.1739	3.5300	2.8240	2.8241	3.4532	2.8400	4.1497
C5	5.0896	3.9644	2.5666	1.5440		1.5454	4.5835	6.0515	5.1482	5.2763	4.2004	2.8435	2.7280	2.1780	2.1693	1.1071	1.1072	2.2033	2.1941	2.1945	4.7189	4.3130	5.6422
C6	6.4511	5.1654	3.9443	2.5656	1.5454		5.5467	7.3355	6.5680	6.6925	5.2418	4.2634	4.1846	2.7967	2.7766	2.1841	2.1832	1.1051	1.1054	1.1055	5.7368	5.0005	6.5726
C7	2.5334	1.5450	2.5627	3.1262	4.5835	5.5467		2.7785	3.5052	2.7937	2.1658	2.8109	3.5076	3.3911	2.8444	4.7781	5.1307	6.5537	5.7320	5.4169	1.1070	1.1038	1.1057
H8	1.1055	2.1998	3.5047	4.7841	6.0515	7.3355	2.7785		1.7905	1.7892	2.5195	3.7948	3.7258	4.8981	5.0634	6.2440	6.1280	8.2282	7.4436	7.5404	3.1921	3.7746	2.5189
H9	1.1055	2.1999	2.7700	4.2071	5.1482	6.5680	3.5052	1.7905		1.7893	2.5215	3.1128	2.4776	4.3904	4.8253	5.3283	4.9584	7.3137	6.7177	6.9974	3.8399	4.3714	3.7615
H10	1.1063	2.1903	2.8004	4.2682	5.2763	6.6925	2.7937	1.7892	1.7893		3.0919	2.5800	3.0764	4.7720	4.5262	5.1743	5.4093	7.4649	7.0544	6.8759	2.6362	3.8331	3.0800
H11	2.1672	1.1087	2.1601	2.8116	4.2004	5.2418	2.1658	2.5195	2.5215	3.0919		3.0777	2.4971	2.5436	3.2451	4.7533	4.3157	6.2116	5.1372	5.5116	3.0907	2.4989	2.5395
H12	2.7717	2.1762	1.1097	2.1791	2.8435	4.2634	2.8109	3.7948	3.1128	2.5800	3.0777		1.7798	3.0920	2.4988	2.6107	3.1967	4.9667	4.8196	4.4517	2.5891	3.2373	3.8013
H13	2.7073	2.1697	1.1092	2.1662	2.7280	4.1846	3.5076	3.7258	2.4776	3.0764	2.4971	1.7798		2.5597	3.0868	3.0164	2.4927	4.8561	4.4283	4.7453	3.7944	3.8738	4.3420
H14	4.2023	2.7893	2.1784	1.1091	2.1780	2.7967	3.3911	4.8981	4.3904	4.7720	2.5436	3.0920	2.5597		1.7800	3.0891	2.5206	3.8116	2.6007	3.1566	4.0101	2.9692	4.2505
H15	4.3248	2.9083	2.1868	1.1067	2.1693	2.7766	2.8444	5.0634	4.8253	4.5262	3.2451	2.4988	3.0868	1.7800		2.5215	3.0819	3.7937	3.1330	2.5800	3.0329	2.3017	3.8843
H16	5.2219	4.2697	2.7862	2.1741	1.1071	2.1841	4.7781	6.2440	5.3283	5.1743	4.7533	2.6107	3.0164	3.0891	2.5215		1.7781	2.5332	3.1053	2.5440	4.6547	4.6287	5.8756
H17	5.1390	4.2023	2.7925	2.1739	1.1072	2.1832	5.1307	6.1280	4.9584	5.4093	4.3157	3.1967	2.4927	2.5206	3.0819	1.7781		2.5329	2.5414	3.1051	5.3520	4.9974	6.1331
H18	7.2871	6.0993	4.7632	3.5300	2.2033	1.1051	6.5537	8.2282	7.3137	7.4649	6.2116	4.9667	4.8561	3.8116	3.7937	2.5332	2.5329		1.7896	1.7896	6.6665	6.0604	7.6025
H19	6.6452	5.2947	4.2621	2.8240	2.1941	1.1054	5.7320	7.4436	6.7177	7.0544	5.1372	4.8196	4.4283	2.6007	3.1330	3.1053	2.5414	1.7896		1.7867	6.1173	5.1058	6.6694
H20	6.7106	5.3489	4.2585	2.8241	2.1945	1.1055	5.4169	7.5404	6.9974	6.8759	5.5116	4.4517	4.7453	3.1566	2.5800	2.5440	3.1051	1.7896	1.7867		5.5147	4.7431	6.4321
H21	2.8281	2.1912	2.7963	3.4532	4.7189	5.7368	1.1070	3.1921	3.8399	2.6362	3.0907	2.5891	3.7944	4.0101	3.0329	4.6547	5.3520	6.6665	6.1173	5.5147		1.7907	1.7901
H22	3.5070	2.2082	2.8652	2.8400	4.3130	5.0005	1.1038	3.7746	4.3714	3.8331	2.4989	3.2373	3.8738	2.9692	2.3017	4.6287	4.9974	6.0604	5.1058	4.7431	1.7907		1.7846
H23	2.7355	2.1933	3.5218	4.1497	5.6422	6.5726	1.1057	2.5189	3.7615	3.0800	2.5395	3.8013	4.3420	4.2505	3.8843	5.8756	6.1331	7.6025	6.6694	6.4321	1.7901	1.7846

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	110.074	C1	C2	C7	110.161
C1	C2	H11	108.414	C2	C1	H8	111.128
C2	C1	H9	111.133	C2	C1	H10	110.333
C2	C3	C4	114.768	C2	C3	H12	108.960
C2	C3	H13	108.486	C2	C7	H21	110.336
C2	C7	H22	111.870	C2	C7	H23	110.579
C3	C2	C7	112.014	C3	C2	H11	107.787
C3	C4	C5	112.434	C3	C4	H14	109.290
C3	C4	H15	110.079	C4	C3	H12	109.309
C4	C3	H13	108.349	C4	C5	C6	112.293
C4	C5	H16	109.075	C4	C5	H17	109.053
C5	C4	H14	109.261	C5	C4	H15	108.722
C5	C6	H18	111.385	C5	C6	H19	110.632
C5	C6	H20	110.661	C6	C5	H16	109.755
C6	C5	H17	109.676	C7	C2	H11	108.277
H8	C1	H9	108.153	H8	C1	H10	107.982
H9	C1	H10	107.989	H12	C3	H13	106.661
H14	C4	H15	106.897	H16	C5	H17	106.835
H18	C6	H19	108.111	H18	C6	H20	108.103
H19	C6	H20	107.822	H21	C7	H22	108.184
H21	C7	H23	107.994	H22	C7	H23	107.745

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP2/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: MP2/CEP-31G*

States and conformations

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