CCCBDB calculation results Page

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

Energy calculated at QCISD/STO-3G

	hartrees
Energy at 0K	-271.697604
Energy at 298.15K	-271.714393
Nuclear repulsion energy	311.630544

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 QCISD/STO-3G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3444	3444	4.59
2	A	3438	3438	7.06
3	A	3437	3437	4.42
4	A	3437	3437	4.67
5	A	3436	3436	8.61
6	A	3435	3435	0.27
7	A	3413	3413	13.13
8	A	3401	3401	0.05
9	A	3395	3395	2.12
10	A	3326	3326	6.44
11	A	3308	3308	12.92
12	A	3302	3302	0.41
13	A	3297	3297	3.55
14	A	3278	3278	3.34
15	A	3276	3276	3.91
16	A	3274	3274	4.09
17	A	1702	1702	0.09
18	A	1698	1698	1.51
19	A	1696	1696	0.40
20	A	1694	1694	0.31
21	A	1692	1692	0.37
22	A	1691	1691	1.23
23	A	1690	1690	0.20
24	A	1681	1681	0.18
25	A	1672	1672	0.14
26	A	1594	1594	0.10
27	A	1591	1591	0.27
28	A	1586	1586	0.67
29	A	1577	1577	0.19
30	A	1534	1534	4.90
31	A	1510	1510	7.47
32	A	1470	1470	0.18
33	A	1443	1443	0.09
34	A	1428	1428	0.16
35	A	1395	1395	18.22
36	A	1369	1369	1.22
37	A	1316	1316	0.38
38	A	1298	1298	3.11
39	A	1266	1266	1.05
40	A	1195	1195	1.08
41	A	1162	1162	0.05
42	A	1139	1139	0.47
43	A	1127	1127	0.38
44	A	1060	1060	0.15
45	A	1045	1045	0.53
46	A	1019	1019	0.71
47	A	1002	1002	0.93
48	A	987	987	0.75
49	A	894	894	0.56
50	A	852	852	0.03
51	A	779	779	2.90
52	A	495	495	0.32
53	A	446	446	0.02
54	A	419	419	0.09
55	A	311	311	0.01
56	A	306	306	0.01
57	A	238	238	0.00
58	A	230	230	0.00
59	A	218	218	0.00
60	A	137	137	0.01
61	A	131	131	0.01
62	A	80	80	0.00
63	A	57	57	0.00

Unscaled Zero Point Vibrational Energy (zpe) 52409.1 cm^-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 52409.1 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 QCISD/STO-3G

A	B	C
0.19437	0.03182	0.02898

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

Geometric Data calculated at QCISD/STO-3G

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.876	-0.929	-0.057
C2	-1.670	0.033	-0.356
C3	-0.334	-0.579	0.218
C4	0.962	0.193	-0.221
C5	2.268	-0.516	0.290
C6	3.566	0.249	-0.143
C7	-1.964	1.464	0.223
H8	-3.818	-0.523	-0.485
H9	-2.697	-1.934	-0.498
H10	-3.017	-1.051	1.039
H11	-1.564	0.121	-1.465
H12	-0.390	-0.605	1.331
H13	-0.252	-1.636	-0.130
H14	0.993	0.262	-1.333
H15	0.937	1.234	0.174
H16	2.236	-0.589	1.402
H17	2.303	-1.556	-0.108
H18	4.473	-0.275	0.232
H19	3.634	0.313	-1.250
H20	3.568	1.283	0.265
H21	-2.039	1.429	1.332
H22	-1.161	2.182	-0.049
H23	-2.925	1.853	-0.178

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		1.5722	2.5812	4.0027	5.1728	6.5497	2.5768	1.1118	1.1117	1.1119	2.1926	2.8654	2.7185	4.2447	4.3904	5.3276	5.2169	7.3837	6.7338	6.8205	2.8617	3.5528	2.7854
C2	1.5722		1.5782	2.6405	4.0285	5.2448	1.5715	2.2227	2.2233	2.2223	1.1173	2.2117	2.2017	2.8454	2.9189	4.3288	4.2860	6.1785	5.3855	5.4202	2.2212	2.2293	2.2176
C3	2.5812	1.5782		1.5712	2.6037	4.0029	2.6141	3.5551	2.8161	2.8456	2.1994	1.1150	1.1150	2.2074	2.2150	2.8297	2.8302	4.8160	4.3231	4.3231	2.8607	2.8951	3.5760
C4	4.0027	2.6405	1.5712		1.5713	2.6056	3.2208	4.8409	4.2412	4.3555	2.8173	2.2079	2.1974	1.1149	1.1137	2.2064	2.2068	3.5703	2.8652	2.8655	3.5982	2.9143	4.2268
C5	5.1728	4.0285	2.6037	1.5713		1.5668	4.6726	6.1356	5.2233	5.3649	4.2631	2.8567	2.7900	2.2059	2.2016	1.1148	1.1147	2.2183	2.2186	2.2186	4.8396	4.3763	5.7268
C6	6.5497	5.2448	4.0029	2.6056	1.5668		5.6736	7.4322	6.6415	6.8134	5.2997	4.3074	4.2579	2.8355	2.8255	2.2032	2.2033	1.1118	1.1118	1.1118	5.9151	5.1081	6.6863
C7	2.5768	1.5715	2.6141	3.2208	4.6726	5.6736		2.8087	3.5500	2.8464	2.1943	2.8254	3.5585	3.5508	2.9102	4.8213	5.2377	6.6672	5.9013	5.5343	1.1119	1.1107	1.1117
H8	1.1118	2.2227	3.5551	4.8409	6.1356	7.4322	2.8087		1.8024	1.8016	2.5405	3.8800	3.7525	4.9476	5.1121	6.3421	6.2188	8.3255	7.5372	7.6401	3.2053	3.8165	2.5567
H9	1.1117	2.2233	2.8161	4.2412	5.2233	6.6415	3.5500	1.8024		1.8018	2.5372	3.2296	2.4900	4.3736	4.8673	5.4547	5.0286	7.3949	6.7588	7.0829	3.8842	4.4156	3.8070
H10	1.1119	2.2223	2.8456	4.3555	5.3649	6.8134	2.8464	1.8016	1.8018		3.1236	2.6800	3.0583	4.8405	4.6482	5.2861	5.4654	7.5730	7.1646	7.0286	2.6814	3.8835	3.1503
H11	2.1926	1.1173	2.1994	2.8173	4.2631	5.2997	2.1943	2.5405	2.5372	3.1236		3.1182	2.5672	2.5643	3.1912	4.8134	4.4280	6.2835	5.2058	5.5390	3.1242	2.5331	2.5511
H12	2.8654	2.2117	1.1150	2.2079	2.8567	4.3074	2.8254	3.8800	3.2296	2.6800	3.1182		1.7932	3.1245	2.5462	2.6279	3.1983	4.9967	4.8680	4.5127	2.6181	3.2039	3.8394
H13	2.7185	2.2017	1.1150	2.1974	2.7900	4.2579	3.5585	3.7525	2.4900	3.0583	2.5672	1.7932		2.5689	3.1215	3.1040	2.5561	4.9303	4.4889	4.8233	3.8368	3.9253	4.3951
H14	4.2447	2.8454	2.2074	1.1149	2.2059	2.8355	3.5508	4.9476	4.3736	4.8405	2.5643	3.1245	2.5689		1.7945	3.1226	2.5538	3.8533	2.6426	3.1980	4.2021	3.1582	4.3832
H15	4.3904	2.9189	2.2150	1.1137	2.2016	2.8255	2.9102	5.1121	4.8673	4.6482	3.1912	2.5462	3.1215	1.7945		2.5534	3.1194	3.8447	3.1857	2.6325	3.1997	2.3130	3.9269
H16	5.3276	4.3288	2.8297	2.2064	1.1148	2.2032	4.8213	6.3421	5.4547	5.2861	4.8134	2.6279	3.1040	3.1226	2.5534		1.7944	2.5433	3.1303	2.5625	4.7285	4.6181	5.9243
H17	5.2169	4.2860	2.8302	2.2068	1.1147	2.2033	5.2377	6.2188	5.0286	5.4654	4.4280	3.1983	2.5561	2.5538	3.1194	1.7944		2.5430	2.5629	3.1303	5.4623	5.0965	6.2412
H18	7.3837	6.1785	4.8160	3.5703	2.2183	1.1118	6.6672	8.3255	7.3949	7.5730	6.2835	4.9967	4.9303	3.8533	3.8447	2.5433	2.5430		1.8018	1.8018	6.8205	6.1526	7.7083
H19	6.7338	5.3855	4.3231	2.8652	2.2186	1.1118	5.9013	7.5372	6.7588	7.1646	5.2058	4.8680	4.4889	2.6426	3.1857	3.1303	2.5629	1.8018		1.8008	6.3321	5.2844	6.8215
H20	6.8205	5.4202	4.3231	2.8655	2.2186	1.1118	5.5343	7.6401	7.0829	7.0286	5.5390	4.5127	4.8233	3.1980	2.6325	2.5625	3.1303	1.8018	1.8008		5.7093	4.8236	6.5324
H21	2.8617	2.2212	2.8607	3.5982	4.8396	5.9151	1.1119	3.2053	3.8842	2.6814	3.1242	2.6181	3.8368	4.2021	3.1997	4.7285	5.4623	6.8205	6.3321	5.7093		1.8018	1.8012
H22	3.5528	2.2293	2.8951	2.9143	4.3763	5.1081	1.1107	3.8165	4.4156	3.8835	2.5331	3.2039	3.9253	3.1582	2.3130	4.6181	5.0965	6.1526	5.2844	4.8236	1.8018		1.7987
H23	2.7854	2.2176	3.5760	4.2268	5.7268	6.6863	1.1117	2.5567	3.8070	3.1503	2.5511	3.8394	4.3951	4.3832	3.9269	5.9243	6.2412	7.7083	6.8215	6.5324	1.8012	1.7987

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	110.034	C1	C2	C7	110.110
C1	C2	H11	108.035	C2	C1	H8	110.649
C2	C1	H9	110.702	C2	C1	H10	110.609
C2	C3	C4	113.944	C2	C3	H12	109.203
C2	C3	H13	108.441	C2	C7	H21	110.576
C2	C7	H22	111.280	C2	C7	H23	110.298
C3	C2	C7	112.186	C3	C2	H11	108.140
C3	C4	C5	111.900	C3	C4	H14	109.349
C3	C4	H15	110.002	C4	C3	H12	109.386
C4	C3	H13	108.580	C4	C5	C6	112.261
C4	C5	H16	109.280	C4	C5	H17	109.308
C5	C4	H14	109.232	C5	C4	H15	108.978
C5	C6	H18	110.671	C5	C6	H19	110.694
C5	C6	H20	110.698	C6	C5	H16	109.332
C6	C5	H17	109.340	C7	C2	H11	108.209
H8	C1	H9	108.315	H8	C1	H10	108.225
H9	C1	H10	108.251	H12	C3	H13	107.057
H14	C4	H15	107.265	H16	C5	H17	107.187
H18	C6	H19	108.257	H18	C6	H20	108.256
H19	C6	H20	108.171	H21	C7	H22	108.326
H21	C7	H23	108.194	H22	C7	H23	108.065

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: QCISD/STO-3G

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: QCISD/STO-3G

States and conformations

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