CCCBDB calculation results Page

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

Energy calculated at QCISD/3-21G

	hartrees
Energy at 0K	-273.625914
Energy at 298.15K	-273.643298
Nuclear repulsion energy	315.162762

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/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3095	3000	32.38
2	A	3087	2992	88.47
3	A	3084	2989	35.55
4	A	3081	2986	64.22
5	A	3080	2985	28.51
6	A	3073	2978	2.32
7	A	3067	2972	15.57
8	A	3044	2950	1.27
9	A	3033	2940	11.20
10	A	3020	2927	51.39
11	A	3019	2926	12.32
12	A	3017	2924	19.18
13	A	3012	2919	20.01
14	A	3012	2919	7.12
15	A	3009	2916	1.35
16	A	2997	2905	9.44
17	A	1587	1538	14.64
18	A	1583	1534	2.47
19	A	1580	1532	3.40
20	A	1578	1530	5.84
21	A	1574	1526	2.42
22	A	1572	1523	1.43
23	A	1569	1521	0.59
24	A	1563	1515	0.10
25	A	1556	1508	0.24
26	A	1479	1434	5.46
27	A	1474	1428	3.06
28	A	1462	1417	6.85
29	A	1421	1377	1.43
30	A	1414	1371	3.49
31	A	1410	1366	1.89
32	A	1385	1342	0.20
33	A	1378	1335	0.36
34	A	1364	1322	0.36
35	A	1328	1287	0.02
36	A	1302	1262	0.78
37	A	1246	1207	0.16
38	A	1221	1183	4.69
39	A	1180	1143	0.86
40	A	1108	1074	6.78
41	A	1084	1051	1.12
42	A	1044	1012	0.26
43	A	1005	974	0.56
44	A	988	958	0.36
45	A	974	944	0.93
46	A	956	926	1.06
47	A	934	905	1.00
48	A	901	873	2.17
49	A	830	804	0.85
50	A	795	770	0.14
51	A	746	723	3.97
52	A	487	472	0.32
53	A	439	425	0.13
54	A	415	402	0.07
55	A	308	298	0.04
56	A	305	296	0.00
57	A	261	253	0.00
58	A	248	240	0.00
59	A	241	233	0.01
60	A	147	143	0.01
61	A	132	128	0.02
62	A	83	81	0.00
63	A	62	61	0.00

Unscaled Zero Point Vibrational Energy (zpe) 48221.8 cm^-1
Scaled (by 0.9692) Zero Point Vibrational Energy (zpe) 46736.6 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 QCISD/3-21G

A	B	C
0.19929	0.03254	0.02966

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

Geometric Data calculated at QCISD/3-21G

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-2.854	-0.906	-0.047
C2	-1.654	0.033	-0.362
C3	-0.337	-0.578	0.200
C4	0.951	0.182	-0.226
C5	2.242	-0.513	0.294
C6	3.528	0.248	-0.136
C7	-1.923	1.449	0.223
H8	-3.788	-0.495	-0.457
H9	-2.690	-1.905	-0.477
H10	-2.968	-1.010	1.044
H11	-1.552	0.117	-1.457
H12	-0.401	-0.603	1.301
H13	-0.256	-1.623	-0.148
H14	0.990	0.238	-1.327
H15	0.924	1.214	0.157
H16	2.198	-0.575	1.393
H17	2.275	-1.545	-0.092
H18	4.431	-0.257	0.240
H19	3.591	0.301	-1.233
H20	3.514	1.275	0.259
H21	-2.006	1.384	1.320
H22	-1.114	2.149	-0.027
H23	-2.867	1.854	-0.174

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		1.5559	2.5502	3.9613	5.1218	6.4863	2.5459	1.1005	1.1005	1.1013	2.1750	2.8147	2.6965	4.2100	4.3369	5.2634	5.1683	7.3189	6.6630	6.7375	2.7983	3.5151	2.7625
C2	1.5559		1.5570	2.6129	3.9880	5.1918	1.5550	2.2008	2.2011	2.1887	1.1034	2.1774	2.1775	2.8222	2.8829	4.2766	4.2423	6.1212	5.3233	5.3510	2.1858	2.2088	2.1955
C3	2.5502	1.5570		1.5546	2.5809	3.9667	2.5741	3.5145	2.7854	2.7968	2.1696	1.1040	1.1038	2.1812	2.1917	2.8018	2.7998	4.7784	4.2721	4.2735	2.8096	2.8447	3.5290
C4	3.9613	2.6129	1.5546		1.5551	2.5797	3.1733	4.7931	4.2045	4.2884	2.7909	2.1858	2.1724	1.1033	1.1011	2.1793	2.1795	3.5378	2.8278	2.8279	3.5470	2.8592	4.1682
C5	5.1218	3.9880	2.5809	1.5551		1.5557	4.6045	6.0766	5.1823	5.2866	4.2261	2.8299	2.7686	2.1813	2.1764	1.1020	1.1019	2.2047	2.1944	2.1945	4.7643	4.2956	5.6494
C6	6.4863	5.1918	3.9667	2.5797	1.5557		5.5942	7.3614	6.5897	6.7214	5.2516	4.2702	4.2216	2.8037	2.7929	2.1878	2.1879	1.0998	1.1003	1.1003	5.8348	5.0182	6.5938
C7	2.5459	1.5550	2.5741	3.1733	4.6045	5.5942		2.7781	3.5109	2.7942	2.1759	2.7731	3.5142	3.5152	2.8583	4.7384	5.1657	6.5790	5.8175	5.4402	1.1015	1.0988	1.1006
H8	1.1005	2.2008	3.5145	4.7931	6.0766	7.3614	2.7781		1.7874	1.7865	2.5247	3.8179	3.7206	4.9121	5.0505	6.2664	6.1640	8.2519	7.4623	7.5476	3.1410	3.7847	2.5389
H9	1.1005	2.2011	2.7854	4.2045	5.1823	6.5897	3.5109	1.7874		1.7870	2.5189	3.1777	2.4724	4.3430	4.8163	5.4003	4.9929	7.3443	6.6999	7.0103	3.8104	4.3727	3.7753
H10	1.1013	2.1887	2.7968	4.2884	5.2866	6.7214	2.7942	1.7865	1.7870		3.0870	2.6113	3.0249	4.7796	4.5695	5.1960	5.3909	7.4802	7.0653	6.9172	2.5948	3.8154	3.1131
H11	2.1750	1.1034	2.1696	2.7909	4.2261	5.2516	2.1759	2.5247	2.5189	3.0870		3.0750	2.5340	2.5489	3.1534	4.7616	4.3901	6.2304	5.1513	5.4730	3.0861	2.5231	2.5280
H12	2.8147	2.1774	1.1040	2.1858	2.8299	4.2702	2.7731	3.8179	3.1777	2.6113	3.0750		1.7779	3.0908	2.5238	2.6012	3.1606	4.9595	4.8145	4.4656	2.5550	3.1380	3.7804
H13	2.6965	2.1775	1.1038	2.1724	2.7686	4.2216	3.5142	3.7206	2.4724	3.0249	2.5340	1.7779		2.5310	3.0875	3.0816	2.5327	4.8972	4.4358	4.7721	3.7763	3.8697	4.3474
H14	4.2100	2.8222	2.1812	1.1033	2.1813	2.8037	3.5152	4.9121	4.3430	4.7796	2.5489	3.0908	2.5310		1.7770	3.0855	2.5206	3.8125	2.6029	3.1556	4.1589	3.1256	4.3376
H15	4.3369	2.8829	2.1917	1.1011	2.1764	2.7929	2.8583	5.0505	4.8163	4.5695	3.1534	2.5238	3.0875	1.7770		2.5203	3.0814	3.8031	3.1425	2.5922	3.1575	2.2505	3.8589
H16	5.2634	4.2766	2.8018	2.1793	1.1020	2.1878	4.7384	6.2664	5.4003	5.1960	4.7616	2.6012	3.0816	3.0855	2.5203		1.7755	2.5332	3.0995	2.5377	4.6393	4.5177	5.8316
H17	5.1683	4.2423	2.7998	2.1795	1.1019	2.1879	5.1657	6.1640	4.9929	5.3909	4.3901	3.1606	2.5327	2.5206	3.0814	1.7755		2.5332	2.5379	3.0996	5.3759	5.0132	6.1636
H18	7.3189	6.1212	4.7784	3.5378	2.2047	1.0998	6.5790	8.2519	7.3443	7.4802	6.2304	4.9595	4.8972	3.8125	3.8031	2.5332	2.5332		1.7850	1.7849	6.7302	6.0503	7.6077
H19	6.6630	5.3233	4.2721	2.8278	2.1944	1.1003	5.8175	7.4623	6.6999	7.0653	5.1513	4.8145	4.4358	2.6029	3.1425	3.0995	2.5379	1.7850		1.7836	6.2464	5.1969	6.7254
H20	6.7375	5.3510	4.2735	2.8279	2.1945	1.1003	5.4402	7.5476	7.0103	6.9172	5.4730	4.4656	4.7721	3.1556	2.5922	2.5377	3.0996	1.7849	1.7836		5.6221	4.7188	6.4214
H21	2.7983	2.1858	2.8096	3.5470	4.7643	5.8348	1.1015	3.1410	3.8104	2.5948	3.0861	2.5550	3.7763	4.1589	3.1575	4.6393	5.3759	6.7302	6.2464	5.6221		1.7867	1.7862
H22	3.5151	2.2088	2.8447	2.8592	4.2956	5.0182	1.0988	3.7847	4.3727	3.8154	2.5231	3.1380	3.8697	3.1256	2.2505	4.5177	5.0132	6.0503	5.1969	4.7188	1.7867		1.7830
H23	2.7625	2.1955	3.5290	4.1682	5.6494	6.5938	1.1006	2.5389	3.7753	3.1131	2.5280	3.7804	4.3474	4.3376	3.8589	5.8316	6.1636	7.6077	6.7254	6.4214	1.7862	1.7830

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	110.014	C1	C2	C7	109.842
C1	C2	H11	108.549	C2	C1	H8	110.722
C2	C1	H9	110.740	C2	C1	H10	109.729
C2	C3	C4	114.219	C2	C3	H12	108.627
C2	C3	H13	108.643	C2	C7	H21	109.552
C2	C7	H22	111.519	C2	C7	H23	110.361
C3	C2	C7	111.613	C3	C2	H11	108.067
C3	C4	C5	112.184	C3	C4	H14	109.115
C3	C4	H15	110.059	C4	C3	H12	109.433
C4	C3	H13	108.415	C4	C5	C6	112.053
C4	C5	H16	109.010	C4	C5	H17	109.034
C5	C4	H14	109.088	C5	C4	H15	108.837
C5	C6	H18	111.084	C5	C6	H19	110.249
C5	C6	H20	110.256	C6	C5	H16	109.638
C6	C5	H17	109.647	C7	C2	H11	108.680
H8	C1	H9	108.608	H8	C1	H10	108.464
H9	C1	H10	108.514	H12	C3	H13	107.281
H14	C4	H15	107.438	H16	C5	H17	107.341
H18	C6	H19	108.446	H18	C6	H20	108.443
H19	C6	H20	108.286	H21	C7	H22	108.590
H21	C7	H23	108.416	H22	C7	H23	108.329

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: QCISD/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: QCISD/3-21G

States and conformations

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