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	-34.754765
Energy at 298.15K	-34.767531
HF Energy	-34.337183
Nuclear repulsion energy	109.698650

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	3135	3029	71.76
2	A	3126	3020	131.16
3	A	3121	3016	178.81
4	A	3119	3014	22.00
5	A	3117	3012	33.16
6	A	3112	3007	3.37
7	A	3082	2978	27.17
8	A	3038	2935	31.07
9	A	3026	2924	21.92
10	A	3018	2917	63.87
11	A	3017	2915	55.53
12	A	3013	2911	33.80
13	A	1541	1489	2.55
14	A	1533	1481	15.89
15	A	1530	1479	7.53
16	A	1526	1474	9.46
17	A	1522	1471	2.74
18	A	1518	1467	0.18
19	A	1508	1457	0.16
20	A	1456	1407	5.01
21	A	1449	1400	9.35
22	A	1437	1389	7.44
23	A	1412	1365	0.54
24	A	1392	1345	2.20
25	A	1351	1306	1.75
26	A	1314	1270	0.77
27	A	1238	1196	0.49
28	A	1222	1181	2.35
29	A	1190	1150	2.43
30	A	1062	1026	0.35
31	A	1050	1014	3.16
32	A	1002	968	7.24
33	A	985	952	0.07
34	A	944	912	1.61
35	A	927	896	0.61
36	A	811	784	1.82
37	A	768	742	1.95
38	A	451	436	0.23
39	A	409	395	0.16
40	A	360	348	0.00
41	A	267	258	0.01
42	A	243	235	0.02
43	A	211	204	0.01
44	A	191	185	0.01
45	A	82	79	0.00

Unscaled Zero Point Vibrational Energy (zpe) 35411.6 cm^-1
Scaled (by 0.9663) Zero Point Vibrational Energy (zpe) 34218.2 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
0.23304	0.10708	0.08177

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	-2.992	-0.636	0.271
H2	-2.227	0.024	-1.220
H3	-2.230	0.991	0.299
C4	-2.137	-0.037	-0.113
H5	-0.778	-1.767	-0.028
H6	-0.663	-0.689	1.404
C7	-0.770	-0.698	0.292
H8	0.353	-0.007	-1.452
C9	0.491	-0.004	-0.343
H10	-0.214	2.112	-0.197
H11	1.571	1.935	-0.300
H12	0.717	1.538	1.237
C13	0.646	1.488	0.127
H14	2.683	-0.361	-0.487
H15	1.704	-1.870	-0.364
H16	1.961	-0.841	1.094
C17	1.791	-0.820	-0.007

Atom - Atom Distances (Å)

	H1	H2	H3	C4	H5	H6	C7	H8	C9	H10	H11	H12	C13	H14	H15	H16	C17
H1		1.8014	1.7964	1.1121	2.5036	2.5908	2.2230	3.8149	3.5925	3.9353	5.2685	4.4065	4.2150	5.7318	4.8969	5.0255	4.7943
H2	1.8014		1.8004	1.1130	2.5939	3.1371	2.2211	2.5905	2.8560	3.0754	4.3500	4.1229	3.4943	4.9792	4.4467	4.8626	4.2810
H3	1.7964	1.8004		1.1108	3.1333	2.5493	2.2327	3.2761	2.9673	2.3595	3.9623	3.1412	2.9239	5.1557	4.9092	4.6429	4.4203
C4	1.1121	1.1130	1.1108		2.2013	2.2133	1.5718	2.8276	2.6382	2.8849	4.2041	3.5284	3.1824	4.8453	4.2636	4.3474	4.0065
H5	2.5036	2.5939	3.1333	2.2013		1.7955	1.1153	2.5310	2.1947	3.9232	4.3928	3.8416	3.5559	3.7639	2.5073	3.1017	2.7380
H6	2.5908	3.1371	2.5493	2.2133	1.7955		1.1165	3.1066	2.2021	3.2567	3.8440	2.6249	2.8427	3.8565	3.1815	2.6466	2.8327
C7	2.2230	2.2211	2.2327	1.5718	1.1153	1.1165		2.1868	1.5732	2.9062	3.5730	2.8470	2.6099	3.5557	2.8151	2.8501	2.5809
H8	3.8149	2.5905	3.2761	2.8276	2.5310	3.1066	2.1868		1.1177	2.5272	2.5653	3.1226	2.1935	2.5466	2.5454	3.1245	2.1948
C9	3.5925	2.8560	2.9673	2.6382	2.1947	2.2021	1.5732	1.1177		2.2352	2.2201	2.2194	1.5716	2.2256	2.2256	2.2195	1.5711
H10	3.9353	3.0754	2.3595	2.8849	3.9232	3.2567	2.9062	2.5272	2.2352		1.7968	1.8035	1.1108	3.8199	4.4229	3.8881	3.5570
H11	5.2685	4.3500	3.9623	4.2041	4.3928	3.8440	3.5730	2.5653	2.2201	1.7968		1.8029	1.1126	2.5577	3.8077	3.1307	2.7794
H12	4.4065	4.1229	3.1412	3.5284	3.8416	2.6249	2.8470	3.1226	2.2194	1.8035	1.8029		1.1141	3.2314	3.8926	2.6887	2.8741
C13	4.2150	3.4943	2.9239	3.1824	3.5559	2.8427	2.6099	2.1935	1.5716	1.1108	1.1126	1.1141		2.8182	3.5544	2.8440	2.5795
H14	5.7318	4.9792	5.1557	4.8453	3.7639	3.8565	3.5557	2.5466	2.2256	3.8199	2.5577	3.2314	2.8182		1.8027	1.8023	1.1123
H15	4.8969	4.4467	4.9092	4.2636	2.5073	3.1815	2.8151	2.5454	2.2256	4.4229	3.8077	3.8926	3.5544	1.8027		1.8028	1.1124
H16	5.0255	4.8626	4.6429	4.3474	3.1017	2.6466	2.8501	3.1245	2.2195	3.8881	3.1307	2.6887	2.8440	1.8023	1.8028		1.1135
C17	4.7943	4.2810	4.4203	4.0065	2.7380	2.8327	2.5809	2.1948	1.5711	3.5570	2.7794	2.8741	2.5795	1.1123	1.1124	1.1135

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	108.110	H1	C4	H3	107.830
H1	C4	C7	110.673	H2	C4	H3	108.120
H2	C4	C7	110.472	H3	C4	C7	111.513
C4	C7	H5	108.823	C4	C7	H6	109.670
C4	C7	C9	114.037	H5	C7	H6	107.124
H5	C7	C9	108.233	H6	C7	C9	108.722
C7	C9	H8	107.506	C7	C9	C13	112.177
C7	C9	C17	110.333	H8	C9	C13	108.111
H8	C9	C17	108.244	C9	C13	H10	111.719
C9	C13	H11	110.439	C9	C13	H12	110.298
C9	C17	H14	110.907	C9	C17	H15	110.907
C9	C17	H16	110.369	H10	C13	H11	107.833
H10	C13	H12	108.303	H11	C13	H12	108.134
C13	C9	C17	110.325	H14	C17	H15	108.251
H14	C17	H16	108.130	H15	C17	H16	108.176

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-)