CCCBDB calculation results Page

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

Energy calculated at CID/3-21G*

	hartrees
Energy at 0K	-273.481048
Energy at 298.15K	-273.498655
Nuclear repulsion energy	317.350049

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 CID/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3209	2986	33.30
2	A	3202	2980	95.27
3	A	3198	2976	34.97
4	A	3196	2974	65.03
5	A	3194	2972	29.63
6	A	3187	2966	2.07
7	A	3183	2961	11.68
8	A	3159	2939	1.34
9	A	3149	2930	9.95
10	A	3135	2917	31.51
11	A	3134	2916	27.65
12	A	3131	2914	27.58
13	A	3128	2911	4.74
14	A	3125	2908	15.57
15	A	3124	2907	8.77
16	A	3113	2897	8.94
17	A	1638	1524	16.97
18	A	1633	1519	4.09
19	A	1631	1517	3.86
20	A	1628	1515	6.85
21	A	1624	1511	3.27
22	A	1621	1509	1.44
23	A	1619	1506	0.54
24	A	1613	1501	0.10
25	A	1605	1494	0.28
26	A	1533	1427	6.70
27	A	1527	1421	4.30
28	A	1515	1410	9.24
29	A	1476	1373	0.91
30	A	1468	1366	3.55
31	A	1462	1360	2.24
32	A	1436	1336	0.27
33	A	1426	1327	0.39
34	A	1412	1314	0.41
35	A	1378	1282	0.12
36	A	1347	1254	0.85
37	A	1289	1199	0.19
38	A	1266	1178	5.24
39	A	1225	1140	1.03
40	A	1150	1070	7.53
41	A	1121	1044	1.39
42	A	1086	1011	0.32
43	A	1046	974	0.63
44	A	1023	952	0.32
45	A	1010	939	0.99
46	A	991	922	1.24
47	A	971	904	1.26
48	A	937	872	2.51
49	A	859	800	1.03
50	A	826	768	0.13
51	A	771	718	4.55
52	A	505	470	0.36
53	A	455	423	0.15
54	A	430	400	0.09
55	A	319	296	0.03
56	A	316	294	0.01
57	A	269	250	0.00
58	A	254	236	0.00
59	A	246	229	0.01
60	A	151	140	0.01
61	A	136	127	0.03
62	A	86	80	0.00
63	A	63	59	0.00

Unscaled Zero Point Vibrational Energy (zpe) 49979.9 cm^-1
Scaled (by 0.9305) Zero Point Vibrational Energy (zpe) 46506.3 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 CID/3-21G*

A	B	C
0.20213	0.03296	0.03004

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

Geometric Data calculated at CID/3-21G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.833	-0.902	-0.046
C2	-1.643	0.033	-0.359
C3	-0.334	-0.573	0.199
C4	0.945	0.183	-0.221
C5	2.228	-0.511	0.288
C6	3.506	0.246	-0.134
C7	-1.915	1.438	0.221
H8	-3.761	-0.498	-0.454
H9	-2.671	-1.893	-0.474
H10	-2.949	-1.007	1.035
H11	-1.544	0.116	-1.445
H12	-0.398	-0.601	1.291
H13	-0.253	-1.608	-0.148
H14	0.983	0.247	-1.313
H15	0.921	1.204	0.164
H16	2.186	-0.581	1.378
H17	2.260	-1.531	-0.101
H18	4.401	-0.258	0.234
H19	3.569	0.307	-1.222
H20	3.496	1.262	0.265
H21	-1.993	1.380	1.309
H22	-1.118	2.137	-0.032
H23	-2.853	1.837	-0.170

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		1.5453	2.5330	3.9355	5.0871	6.4432	2.5284	1.0914	1.0914	1.0922	2.1579	2.7944	2.6771	4.1819	4.3100	5.2278	5.1327	7.2681	6.6211	6.6958	2.7835	3.4902	2.7417
C2	1.5453		1.5467	2.5969	3.9623	5.1588	1.5444	2.1855	2.1860	2.1746	1.0938	2.1621	2.1608	2.8023	2.8673	4.2499	4.2134	6.0801	5.2908	5.3205	2.1720	2.1937	2.1800
C3	2.5330	1.5467		1.5442	2.5638	3.9403	2.5581	3.4899	2.7673	2.7798	2.1541	1.0946	1.0943	2.1655	2.1757	2.7827	2.7818	4.7452	4.2458	4.2467	2.7924	2.8304	3.5052
C4	3.9355	2.5969	1.5442		1.5446	2.5629	3.1545	4.7615	4.1779	4.2617	2.7747	2.1696	2.1560	1.0940	1.0917	2.1638	2.1641	3.5130	2.8109	2.8111	3.5225	2.8478	4.1429
C5	5.0871	3.9623	2.5638	1.5446		1.5447	4.5786	6.0349	5.1468	5.2537	4.1979	2.8120	2.7469	2.1651	2.1600	1.0927	1.0926	2.1884	2.1795	2.1796	4.7361	4.2785	5.6154
C6	6.4432	5.1588	3.9403	2.5629	1.5447		5.5617	7.3124	6.5459	6.6788	5.2190	4.2416	4.1912	2.7850	2.7733	2.1707	2.1707	1.0908	1.0913	1.0913	5.7973	4.9966	6.5549
C7	2.5284	1.5444	2.5581	3.1545	4.5786	5.5617		2.7591	3.4861	2.7772	2.1590	2.7577	3.4893	3.4882	2.8458	4.7155	5.1336	6.5393	5.7824	5.4133	1.0924	1.0897	1.0915
H8	1.0914	2.1855	3.4899	4.7615	6.0349	7.3124	2.7591		1.7712	1.7707	2.5054	3.7903	3.6927	4.8785	5.0201	6.2241	6.1201	8.1946	7.4147	7.5017	3.1235	3.7563	2.5208
H9	1.0914	2.1860	2.7673	4.1779	5.1468	6.5459	3.4861	1.7712		1.7713	2.5002	3.1542	2.4568	4.3169	4.7858	5.3617	4.9588	7.2929	6.6591	6.9661	3.7878	4.3420	3.7466
H10	1.0922	2.1746	2.7798	4.2617	5.2537	6.6788	2.7772	1.7707	1.7713		3.0637	2.5958	3.0048	4.7480	4.5415	5.1646	5.3575	7.4312	7.0221	6.8757	2.5856	3.7919	3.0900
H11	2.1579	1.0938	2.1541	2.7747	4.1979	5.2190	2.1590	2.5054	2.5002	3.0637		3.0517	2.5140	2.5335	3.1384	4.7298	4.3581	6.1885	5.1216	5.4435	3.0631	2.5031	2.5101
H12	2.7944	2.1621	1.0946	2.1696	2.8120	4.2416	2.7577	3.7903	3.1542	2.5958	3.0517		1.7617	3.0668	2.5039	2.5861	3.1416	4.9258	4.7832	4.4367	2.5433	3.1250	3.7554
H13	2.6771	2.1608	1.0943	2.1560	2.7469	4.1912	3.4893	3.6927	2.4568	3.0048	2.5140	1.7617		2.5146	3.0630	3.0550	2.5148	4.8604	4.4078	4.7386	3.7515	3.8451	4.3155
H14	4.1819	2.8023	2.1655	1.0940	2.1651	2.7850	3.4882	4.8785	4.3169	4.7480	2.5335	3.0668	2.5146		1.7613	3.0617	2.5025	3.7854	2.5888	3.1356	4.1246	3.1028	4.3065
H15	4.3100	2.8673	2.1757	1.0917	2.1600	2.7733	2.8458	5.0201	4.7858	4.5415	3.1384	2.5039	3.0630	1.7613		2.5024	3.0576	3.7753	3.1211	2.5773	3.1357	2.2503	3.8408
H16	5.2278	4.2499	2.7827	2.1638	1.0927	2.1707	4.7155	6.2241	5.3617	5.1646	4.7298	2.5861	3.0550	3.0617	2.5024		1.7597	2.5132	3.0758	2.5196	4.6170	4.5046	5.7995
H17	5.1327	4.2134	2.7818	2.1641	1.0926	2.1707	5.1336	6.1201	4.9588	5.3575	4.3581	3.1416	2.5148	2.5025	3.0576	1.7597		2.5129	2.5199	3.0759	5.3435	4.9874	6.1232
H18	7.2681	6.0801	4.7452	3.5130	2.1884	1.0908	6.5393	8.1946	7.2929	7.4312	6.1885	4.9258	4.8604	3.7854	3.7753	2.5132	2.5129		1.7692	1.7692	6.6872	6.0216	7.5607
H19	6.6211	5.2908	4.2458	2.8109	2.1795	1.0913	5.7824	7.4147	6.6591	7.0221	5.1216	4.7832	4.4078	2.5888	3.1211	3.0758	2.5199	1.7692		1.7683	6.2045	5.1705	6.6851
H20	6.6958	5.3205	4.2467	2.8111	2.1796	1.0913	5.4133	7.5017	6.9661	6.8757	5.4435	4.4367	4.7386	3.1356	2.5773	2.5196	3.0759	1.7692	1.7683		5.5884	4.7048	6.3891
H21	2.7835	2.1720	2.7924	3.5225	4.7361	5.7973	1.0924	3.1235	3.7878	2.5856	3.0631	2.5433	3.7515	4.1246	3.1357	4.6170	5.3435	6.6872	6.2045	5.5884		1.7711	1.7704
H22	3.4902	2.1937	2.8304	2.8478	4.2785	4.9966	1.0897	3.7563	4.3420	3.7919	2.5031	3.1250	3.8451	3.1028	2.2503	4.5046	4.9874	6.0216	5.1705	4.7048	1.7711		1.7665
H23	2.7417	2.1800	3.5052	4.1429	5.6154	6.5549	1.0915	2.5208	3.7466	3.0900	2.5101	3.7554	4.3155	4.3065	3.8408	5.7995	6.1232	7.5607	6.6851	6.3891	1.7704	1.7665

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	110.007	C1	C2	C7	109.836
C1	C2	H11	108.486	C2	C1	H8	110.787
C2	C1	H9	110.832	C2	C1	H10	109.886
C2	C3	C4	114.315	C2	C3	H12	108.677
C2	C3	H13	108.592	C2	C7	H21	109.728
C2	C7	H22	111.609	C2	C7	H23	110.413
C3	C2	C7	111.698	C3	C2	H11	108.097
C3	C4	C5	112.207	C3	C4	H14	109.150
C3	C4	H15	110.075	C4	C3	H12	109.434
C4	C3	H13	108.399	C4	C5	C6	112.118
C4	C5	H16	109.057	C4	C5	H17	109.089
C5	C4	H14	109.086	C5	C4	H15	108.818
C5	C6	H18	111.104	C5	C6	H19	110.366
C5	C6	H20	110.376	C6	C5	H16	109.590
C6	C5	H17	109.597	C7	C2	H11	108.635
H8	C1	H9	108.468	H8	C1	H10	108.369
H9	C1	H10	108.425	H12	C3	H13	107.188
H14	C4	H15	107.381	H16	C5	H17	107.264
H18	C6	H19	108.343	H18	C6	H20	108.338
H19	C6	H20	108.228	H21	C7	H22	108.518
H21	C7	H23	108.323	H22	C7	H23	108.165

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: CID/3-21G*

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: CID/3-21G*

States and conformations

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