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	-35.049918
Energy at 298.15K	-35.062823
HF Energy	-34.425388
Nuclear repulsion energy	111.172992

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	3187	3026	45.77
2	A	3176	3016	66.92
3	A	3173	3012	72.09
4	A	3170	3010	29.39
5	A	3169	3009	56.37
6	A	3164	3004	3.29
7	A	3135	2976	22.87
8	A	3090	2934	24.59
9	A	3082	2926	24.28
10	A	3073	2918	33.26
11	A	3072	2917	46.70
12	A	3068	2913	23.06
13	A	1545	1467	4.48
14	A	1533	1456	19.99
15	A	1531	1454	4.06
16	A	1527	1450	8.67
17	A	1522	1445	2.13
18	A	1517	1440	0.10
19	A	1507	1431	0.27
20	A	1449	1376	8.14
21	A	1445	1372	2.01
22	A	1439	1366	10.44
23	A	1420	1348	0.91
24	A	1389	1318	0.41
25	A	1344	1276	0.87
26	A	1317	1251	1.48
27	A	1231	1169	1.27
28	A	1224	1163	0.83
29	A	1196	1136	2.20
30	A	1086	1031	0.11
31	A	1053	1000	2.75
32	A	1001	950	6.58
33	A	988	938	0.37
34	A	948	900	0.70
35	A	944	896	1.87
36	A	815	774	0.40
37	A	779	740	3.52
38	A	457	434	0.21
39	A	416	395	0.16
40	A	371	353	0.00
41	A	283	269	0.01
42	A	261	248	0.01
43	A	229	218	0.01
44	A	209	199	0.01
45	A	95	90	0.00

Unscaled Zero Point Vibrational Energy (zpe) 35816.3 cm^-1
Scaled (by 0.9494) Zero Point Vibrational Energy (zpe) 34004.0 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
0.24035	0.11057	0.08447

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)
H1	-2.949	-0.635	0.275
H2	-2.201	0.042	-1.203
H3	-2.194	0.980	0.319
C4	-2.102	-0.035	-0.104
H5	-0.767	-1.749	-0.051
H6	-0.642	-0.701	1.380
C7	-0.755	-0.692	0.278
H8	0.355	-0.006	-1.445
C9	0.483	-0.004	-0.344
H10	-0.223	2.084	-0.194
H11	1.550	1.912	-0.294
H12	0.700	1.507	1.228
C13	0.631	1.461	0.125
H14	2.653	-0.345	-0.470
H15	1.685	-1.847	-0.353
H16	1.922	-0.820	1.093
C17	1.761	-0.801	-0.001

Atom - Atom Distances (Å)

	H1	H2	H3	C4	H5	H6	C7	H8	C9	H10	H11	H12	C13	H14	H15	H16	C17
H1		1.7892	1.7836	1.1052	2.4716	2.5593	2.1955	3.7782	3.5445	3.8792	5.2013	4.3377	4.1516	5.6587	4.8311	4.9433	4.7217
H2	1.7892		1.7879	1.1060	2.5668	3.1070	2.1957	2.5680	2.8185	3.0172	4.2886	4.0588	3.4346	4.9238	4.4031	4.7972	4.2252
H3	1.7836	1.7879		1.1038	3.1021	2.5221	2.2067	3.2534	2.9286	2.3168	3.9066	3.0791	2.8724	5.0863	4.8468	4.5592	4.3500
C4	1.1052	1.1060	1.1038		2.1730	2.1856	1.5466	2.7996	2.5964	2.8339	4.1428	3.4648	3.1241	4.7787	4.2053	4.2712	3.9398
H5	2.4716	2.5668	3.1021	2.1730		1.7788	1.1077	2.4987	2.1670	3.8748	4.3397	3.7940	3.5063	3.7208	2.4729	3.0670	2.7010
H6	2.5593	3.1070	2.5221	2.1856	1.7788		1.1084	3.0760	2.1737	3.2264	3.7991	2.5882	2.8056	3.7953	3.1200	2.5832	2.7742
C7	2.1955	2.1957	2.2067	1.5466	1.1077	1.1084		2.1612	1.5464	2.8654	3.5235	2.8025	2.5647	3.5054	2.7720	2.8012	2.5337
H8	3.7782	2.5680	3.2534	2.7996	2.4987	3.0760	2.1612		1.1088	2.5041	2.5359	3.0915	2.1664	2.5190	2.5197	3.0922	2.1667
C9	3.5445	2.8185	2.9286	2.5964	2.1670	2.1737	1.5464	1.1088		2.2096	2.1933	2.1916	1.5454	2.1997	2.2000	2.1912	1.5449
H10	3.8792	3.0172	2.3168	2.8339	3.8748	3.2264	2.8654	2.5041	2.2096		1.7841	1.7909	1.1040	3.7745	4.3725	3.8332	3.5074
H11	5.2013	4.2886	3.9066	4.1428	4.3397	3.7991	3.5235	2.5359	2.1933	1.7841		1.7899	1.1057	2.5179	3.7614	3.0863	2.7371
H12	4.3377	4.0588	3.0791	3.4648	3.7940	2.5882	2.8025	3.0915	2.1916	1.7909	1.7899		1.1070	3.1823	3.8367	2.6322	2.8229
C13	4.1516	3.4346	2.8724	3.1241	3.5063	2.8056	2.5647	2.1664	1.5454	1.1040	1.1057	1.1070		2.7753	3.5045	2.7946	2.5323
H14	5.6587	4.9238	5.0863	4.7787	3.7208	3.7953	3.5054	2.5190	2.1997	3.7745	2.5179	3.1823	2.7753		1.7903	1.7891	1.1054
H15	4.8311	4.4031	4.8468	4.2053	2.4729	3.1200	2.7720	2.5197	2.2000	4.3725	3.7614	3.8367	3.5045	1.7903		1.7894	1.1056
H16	4.9433	4.7972	4.5592	4.2712	3.0670	2.5832	2.8012	3.0922	2.1912	3.8332	3.0863	2.6322	2.7946	1.7891	1.7894		1.1064
C17	4.7217	4.2252	4.3500	3.9398	2.7010	2.7742	2.5337	2.1667	1.5449	3.5074	2.7371	2.8229	2.5323	1.1054	1.1056	1.1064

picture of Butane, 2-methyl- state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
H1	C4	H2	108.029	H1	C4	H3	107.697
H1	C4	C7	110.676	H2	C4	H3	108.015
H2	C4	C7	110.644	H3	C4	C7	111.640
C4	C7	H5	108.782	C4	C7	H6	109.715
C4	C7	C9	114.167	H5	C7	H6	106.774
H5	C7	C9	108.335	H6	C7	C9	108.803
C7	C9	H8	107.825	C7	C9	C13	112.103
C7	C9	C17	110.096	H8	C9	C13	108.291
H8	C9	C17	108.345	C9	C13	H10	111.953
C9	C13	H11	110.556	C9	C13	H12	110.341
C9	C17	H14	111.110	C9	C17	H15	111.124
C9	C17	H16	110.388	H10	C13	H11	107.683
H10	C13	H12	108.189	H11	C13	H12	107.983
C13	C9	C17	110.065	H14	C17	H15	108.138
H14	C17	H16	107.968	H15	C17	H16	107.990

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

All results from a given calculation for C₅H₁₂ (Butane, 2-methyl-)

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 C5H12 (Butane, 2-methyl-)

using model chemistry: MP2/CEP-31G*

States and conformations

All results from a given calculation for C₅H₁₂ (Butane, 2-methyl-)