CCCBDB calculation results Page

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

Energy calculated at HF/CEP-31G*

	hartrees
Energy at 0K	-34.426978
Energy at 298.15K	-34.440139
Nuclear repulsion energy	111.607694

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 HF/CEP-31G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3291	2955	94.87
2	A	3279	2945	196.48
3	A	3274	2940	207.45
4	A	3270	2936	31.74
5	A	3269	2936	24.37
6	A	3262	2930	1.47
7	A	3237	2907	22.23
8	A	3216	2888	7.34
9	A	3208	2881	62.11
10	A	3204	2877	43.31
11	A	3202	2876	101.07
12	A	3197	2871	6.57
13	A	1642	1475	3.25
14	A	1634	1468	10.11
15	A	1633	1466	1.45
16	A	1627	1461	7.91
17	A	1623	1457	1.24
18	A	1617	1452	0.16
19	A	1611	1447	0.27
20	A	1556	1397	3.16
21	A	1555	1396	0.99
22	A	1546	1389	2.66
23	A	1522	1367	0.19
24	A	1482	1331	2.30
25	A	1437	1291	4.52
26	A	1401	1259	2.19
27	A	1300	1168	0.21
28	A	1291	1160	2.04
29	A	1260	1132	1.87
30	A	1123	1008	0.36
31	A	1100	988	1.26
32	A	1055	948	2.03
33	A	1036	930	0.06
34	A	996	895	0.43
35	A	983	882	0.48
36	A	849	763	0.33
37	A	810	727	1.29
38	A	480	431	0.06
39	A	434	390	0.03
40	A	388	348	0.04
41	A	286	256	0.00
42	A	278	250	0.00
43	A	242	218	0.00
44	A	228	204	0.01
45	A	98	88	0.00

Unscaled Zero Point Vibrational Energy (zpe) 37516.2 cm^-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 33689.5 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 HF/CEP-31G*

A	B	C
0.24155	0.11034	0.08443

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

Geometric Data calculated at HF/CEP-31G*

Point Group is C₁

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
H1	-2.939	-0.620	0.301
H2	-2.222	-0.028	-1.199
H3	-2.208	0.981	0.250
C4	-2.109	-0.044	-0.112
H5	-0.771	-1.727	0.008
H6	-0.660	-0.649	1.383
C7	-0.760	-0.671	0.294
H8	0.346	-0.006	-1.428
C9	0.481	-0.005	-0.342
H10	-0.182	2.084	-0.166
H11	1.560	1.892	-0.325
H12	0.770	1.509	1.206
C13	0.663	1.455	0.119
H14	2.632	-0.383	-0.485
H15	1.658	-1.851	-0.372
H16	1.924	-0.855	1.061
C17	1.748	-0.822	-0.017

Atom - Atom Distances (Å)

	H1	H2	H3	C4	H5	H6	C7	H8	C9	H10	H11	H12	C13	H14	H15	H16	C17
H1		1.7650	1.7606	1.0920	2.4524	2.5230	2.1804	3.7631	3.5340	3.8901	5.1913	4.3710	4.1611	5.6316	4.8073	4.9277	4.7025
H2	1.7650		1.7654	1.0932	2.5388	3.0807	2.1864	2.5784	2.8355	3.1129	4.3311	4.1346	3.5012	4.9191	4.3663	4.7935	4.2174
H3	1.7606	1.7654		1.0912	3.0749	2.5172	2.1978	3.2110	2.9245	2.3441	3.9194	3.1716	2.9126	5.0818	4.8328	4.5934	4.3555
C4	1.0920	1.0932	1.0912		2.1530	2.1675	1.5420	2.7854	2.5998	2.8711	4.1539	3.5257	3.1592	4.7673	4.1862	4.2769	3.9353
H5	2.4524	2.5388	3.0749	2.1530		1.7510	1.0934	2.5036	2.1568	3.8600	4.3174	3.7786	3.4919	3.6917	2.4619	3.0218	2.6766
H6	2.5230	3.0807	2.5172	2.1675	1.7510		1.0941	3.0538	2.1660	3.1778	3.7820	2.5945	2.7886	3.7944	3.1466	2.6119	2.7910
C7	2.1804	2.1864	2.1978	1.5420	1.0934	1.0941		2.1514	1.5448	2.8529	3.5124	2.8150	2.5646	3.4918	2.7716	2.7969	2.5312
H8	3.7631	2.5784	3.2110	2.7854	2.5036	3.0538	2.1514		1.0939	2.4977	2.5085	3.0675	2.1510	2.5014	2.4984	3.0666	2.1494
C9	3.5340	2.8355	2.9245	2.5998	2.1568	2.1660	1.5448	1.0939		2.1992	2.1831	2.1846	1.5425	2.1887	2.1897	2.1846	1.5420
H10	3.8901	3.1129	2.3441	2.8711	3.8600	3.1778	2.8529	2.4977	2.1992		1.7603	1.7662	1.0909	3.7557	4.3493	3.8182	3.4917
H11	5.1913	4.3311	3.9194	4.1539	4.3174	3.7820	3.5124	2.5085	2.1831	1.7603		1.7651	1.0924	2.5194	3.7447	3.0980	2.7375
H12	4.3710	4.1346	3.1716	3.5257	3.7786	2.5945	2.8150	3.0675	2.1846	1.7662	1.7651		1.0938	3.1471	3.8170	2.6343	2.8081
C13	4.1611	3.5012	2.9126	3.1592	3.4919	2.7886	2.5646	2.1510	1.5425	1.0909	1.0924	1.0938		2.7606	3.4879	2.7956	2.5263
H14	5.6316	4.9191	5.0818	4.7673	3.6917	3.7944	3.4918	2.5014	2.1887	3.7557	2.5194	3.1471	2.7606		1.7656	1.7647	1.0921
H15	4.8073	4.3663	4.8328	4.1862	2.4619	3.1466	2.7716	2.4984	2.1897	4.3493	3.7447	3.8170	3.4879	1.7656		1.7655	1.0924
H16	4.9277	4.7935	4.5934	4.2769	3.0218	2.6119	2.7969	3.0666	2.1846	3.8182	3.0980	2.6343	2.7956	1.7647	1.7655		1.0933
C17	4.7025	4.2174	4.3555	3.9353	2.6766	2.7910	2.5312	2.1494	1.5420	3.4917	2.7375	2.8081	2.5263	1.0921	1.0924	1.0933

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	107.742	H1	C4	H3	107.497
H1	C4	C7	110.579	H2	C4	H3	107.842
H2	C4	C7	110.981	H3	C4	C7	112.022
C4	C7	H5	108.356	C4	C7	H6	109.440
C4	C7	C9	114.754	H5	C7	H6	106.354
H5	C7	C9	108.464	H6	C7	C9	109.136
C7	C9	H8	108.017	C7	C9	C13	112.342
C7	C9	C17	110.176	H8	C9	C13	108.142
H8	C9	C17	108.054	C9	C13	H10	112.119
C9	C13	H11	110.735	C9	C13	H12	110.775
C9	C17	H14	111.239	C9	C17	H15	111.299
C9	C17	H16	110.841	H10	C13	H11	107.457
H10	C13	H12	107.887	H11	C13	H12	107.686
C13	C9	C17	109.977	H14	C17	H15	107.843
H14	C17	H16	107.702	H15	C17	H16	107.754

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G* Charges (e)

Number	Element	Mulliken
1	H	0.134
2	H	0.095
3	H	0.096
4	C	-0.326
5	H	0.094
6	H	0.079
7	C	-0.197
8	H	0.076
9	C	0.058
10	H	0.125
11	H	0.120
12	H	0.094
13	C	-0.417
14	H	0.129
15	H	0.114
16	H	0.087
17	C	-0.359

Electric dipole moments
Electric dipole components in Debye
(What's a Debye? See section VII.A.3)

	x	y	z	Total
	-0.024	-0.056	-0.073	0.095
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-35.920	0.343	-0.238
y	0.343	-35.428	0.100
z	-0.238	0.100	-34.456

Traceless
	x	y	z
x	-0.978	0.343	-0.238
y	0.343	-0.240	0.100
z	-0.238	0.100	1.218

Polar
3z²-r²	2.435
x²-y²	-0.492
xy	0.343
xz	-0.238
yz	0.100

Polarizabilities
Components of the polarizability tensor.
Units are Å³ (Angstrom cubed)
Change units.

	x	y	z
x	8.430	-0.104	0.044
y	-0.104	7.576	0.014
z	0.044	0.014	6.863

<r²> (average value of r²) Å²

<r²>	134.851
(<r²>)^1/2	11.613

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

using model chemistry: HF/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: HF/CEP-31G*

States and conformations

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