CCCBDB calculation results Page

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

Energy calculated at MP2/CEP-121G*

	hartrees
Energy at 0K	-35.114882
Energy at 298.15K	-35.127798
HF Energy	-34.441721
Nuclear repulsion energy	111.787532

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-121G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3166	3017	36.53
2	A	3156	3007	55.02
3	A	3151	3002	56.91
4	A	3148	2999	38.90
5	A	3144	2995	60.58
6	A	3139	2990	4.16
7	A	3102	2956	24.70
8	A	3060	2916	22.56
9	A	3052	2908	46.51
10	A	3049	2905	24.48
11	A	3048	2904	40.84
12	A	3043	2900	7.68
13	A	1555	1482	3.62
14	A	1544	1471	19.90
15	A	1540	1467	4.02
16	A	1537	1464	9.29
17	A	1532	1459	1.63
18	A	1525	1453	0.11
19	A	1516	1444	0.34
20	A	1452	1384	7.45
21	A	1444	1376	4.66
22	A	1437	1369	8.56
23	A	1412	1345	0.77
24	A	1387	1322	0.87
25	A	1340	1277	1.34
26	A	1315	1253	1.61
27	A	1227	1169	0.16
28	A	1216	1158	0.98
29	A	1190	1134	2.01
30	A	1077	1026	0.28
31	A	1044	995	1.93
32	A	987	941	2.37
33	A	980	933	0.56
34	A	941	896	0.84
35	A	932	888	0.69
36	A	807	769	0.09
37	A	773	737	1.89
38	A	456	435	0.11
39	A	419	400	0.08
40	A	373	356	0.03
41	A	289	276	0.00
42	A	254	242	0.00
43	A	226	215	0.00
44	A	204	194	0.03
45	A	98	93	0.00

Unscaled Zero Point Vibrational Energy (zpe) 35642.9 cm^-1
Scaled (by 0.9528) Zero Point Vibrational Energy (zpe) 33960.6 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 MP2/CEP-121G*

A	B	C
0.24315	0.11170	0.08521

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

Geometric Data calculated at MP2/CEP-121G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
H1	-2.924	-0.672	0.260
H2	-2.191	0.062	-1.177
H3	-2.190	0.932	0.369
C4	-2.089	-0.056	-0.092
H5	-0.749	-1.754	-0.091
H6	-0.620	-0.746	1.351
C7	-0.741	-0.712	0.258
H8	0.369	-0.011	-1.445
C9	0.487	-0.006	-0.350
H10	-0.243	2.065	-0.227
H11	1.519	1.915	-0.266
H12	0.629	1.504	1.214
C13	0.600	1.456	0.117
H14	2.649	-0.319	-0.470
H15	1.711	-1.820	-0.336
H16	1.931	-0.779	1.086
C17	1.771	-0.777	-0.000

Atom - Atom Distances (Å)

	H1	H2	H3	C4	H5	H6	C7	H8	C9	H10	H11	H12	C13	H14	H15	H16	C17
H1		1.7729	1.7674	1.0957	2.4541	2.5502	2.1832	3.7664	3.5279	3.8619	5.1682	4.2743	4.1190	5.6319	4.8114	4.9259	4.7031
H2	1.7729		1.7739	1.0969	2.5609	3.0846	2.1820	2.5746	2.8031	2.9505	4.2457	3.9684	3.3770	4.9064	4.4126	4.7772	4.2173
H3	1.7674	1.7739		1.0946	3.0828	2.4995	2.1944	3.2752	2.9258	2.3301	3.8895	2.9985	2.8499	5.0687	4.8256	4.5201	4.3302
C4	1.0957	1.0969	1.0946		2.1632	2.1717	1.5393	2.8061	2.5889	2.8146	4.1150	3.3949	3.0917	4.7608	4.1962	4.2512	3.9279
H5	2.4541	2.5609	3.0828	2.1632		1.7640	1.0991	2.4743	2.1566	3.8546	4.3172	3.7705	3.4884	3.7085	2.4728	3.0852	2.7042
H6	2.5502	3.0846	2.4995	2.1717	1.7640		1.1006	3.0555	2.1599	3.2456	3.7779	2.5773	2.8040	3.7667	3.0710	2.5652	2.7467
C7	2.1832	2.1820	2.1944	1.5393	1.0991	1.1006		2.1499	1.5409	2.8622	3.5047	2.7750	2.5530	3.4898	2.7551	2.7984	2.5260
H8	3.7664	2.5746	3.2752	2.8061	2.4743	3.0555	2.1499		1.1015	2.4830	2.5342	3.0708	2.1550	2.4992	2.5103	3.0717	2.1541
C9	3.5279	2.8031	2.9258	2.5889	2.1566	2.1599	1.5409	1.1015		2.1986	2.1823	2.1778	1.5387	2.1888	2.1885	2.1786	1.5387
H10	3.8619	2.9505	2.3301	2.8146	3.8546	3.2456	2.8622	2.4830	2.1986		1.7690	1.7753	1.0948	3.7562	4.3495	3.8133	3.4909
H11	5.1682	4.2457	3.8895	4.1150	4.3172	3.7779	3.5047	2.5342	2.1823	1.7690		1.7748	1.0964	2.5122	3.7404	3.0427	2.7174
H12	4.2743	3.9684	2.9985	3.3949	3.7705	2.5773	2.7750	3.0708	2.1778	1.7753	1.7748		1.0984	3.1999	3.8233	2.6317	2.8253
C13	4.1190	3.3770	2.8499	3.0917	3.4884	2.8040	2.5530	2.1550	1.5387	1.0948	1.0964	1.0984		2.7746	3.4888	2.7769	2.5250
H14	5.6319	4.9064	5.0687	4.7608	3.7085	3.7667	3.4898	2.4992	2.1888	3.7562	2.5122	3.1999	2.7746		1.7751	1.7743	1.0965
H15	4.8114	4.4126	4.8256	4.1962	2.4728	3.0710	2.7551	2.5103	2.1885	4.3495	3.7404	3.8233	3.4888	1.7751		1.7755	1.0966
H16	4.9259	4.7772	4.5201	4.2512	3.0852	2.5652	2.7984	3.0717	2.1786	3.8133	3.0427	2.6317	2.7769	1.7743	1.7755		1.0979
C17	4.7031	4.2173	4.3302	3.9279	2.7042	2.7467	2.5260	2.1541	1.5387	3.4909	2.7174	2.8253	2.5250	1.0965	1.0966	1.0979

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	107.916	H1	C4	H3	107.596
H1	C4	C7	110.766	H2	C4	H3	108.087
H2	C4	C7	110.599	H3	C4	C7	111.730
C4	C7	H5	109.005	C4	C7	H6	109.578
C4	C7	C9	114.381	H5	C7	H6	106.637
H5	C7	C9	108.391	H6	C7	C9	108.562
C7	C9	H8	107.741	C7	C9	C13	111.995
C7	C9	C17	110.219	H8	C9	C13	108.279
H8	C9	C17	108.208	C9	C13	H10	112.098
C9	C13	H11	110.698	C9	C13	H12	110.231
C9	C17	H14	111.212	C9	C17	H15	111.183
C9	C17	H16	110.326	H10	C13	H11	107.663
H10	C13	H12	108.082	H11	C13	H12	107.921
C13	C9	C17	110.271	H14	C17	H15	108.072
H14	C17	H16	107.911	H15	C17	H16	108.008

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP2/CEP-121G*

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-121G*

States and conformations

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