CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	C2H	¹A_g

Energy calculated at mPW1PW91/6-31G(2df,p)

	hartrees
Energy at 0K	-237.048092
Energy at 298.15K	-237.063108
Nuclear repulsion energy	262.945305

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 mPW1PW91/6-31G(2df,p)

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3152	3009	0.00
2	A_g	3128	2987	0.00
3	A_g	3055	2917	0.00
4	A_g	3009	2873	0.00
5	A_g	1525	1456	0.00
6	A_g	1506	1438	0.00
7	A_g	1421	1357	0.00
8	A_g	1382	1319	0.00
9	A_g	1220	1165	0.00
10	A_g	1198	1144	0.00
11	A_g	964	920	0.00
12	A_g	766	731	0.00
13	A_g	496	473	0.00
14	A_g	382	365	0.00
15	A_g	236	225	0.00
16	A_u	3151	3009	50.22
17	A_u	3124	2982	1.68
18	A_u	3051	2912	45.15
19	A_u	1504	1436	4.82
20	A_u	1483	1416	0.81
21	A_u	1400	1337	10.06
22	A_u	1340	1280	3.31
23	A_u	1100	1051	1.68
24	A_u	974	930	0.58
25	A_u	926	884	2.07
26	A_u	299	286	0.01
27	A_u	196	187	0.03
28	A_u	60	57	0.00
29	B_g	3139	2997	0.00
30	B_g	3124	2983	0.00
31	B_g	3049	2911	0.00
32	B_g	1491	1424	0.00
33	B_g	1483	1416	0.00
34	B_g	1397	1334	0.00
35	B_g	1353	1292	0.00
36	B_g	1186	1132	0.00
37	B_g	967	923	0.00
38	B_g	918	877	0.00
39	B_g	425	406	0.00
40	B_g	194	186	0.00
41	B_u	3142	3000	69.73
42	B_u	3130	2988	117.19
43	B_u	3052	2914	57.49
44	B_u	3024	2887	34.28
45	B_u	1510	1442	15.31
46	B_u	1501	1433	16.66
47	B_u	1414	1350	12.87
48	B_u	1306	1246	6.42
49	B_u	1182	1128	8.17
50	B_u	997	952	6.24
51	B_u	887	847	2.28
52	B_u	404	386	0.12
53	B_u	345	330	0.13
54	B_u	213	203	0.03

Unscaled Zero Point Vibrational Energy (zpe) 41441.6 cm^-1
Scaled (by 0.9547) Zero Point Vibrational Energy (zpe) 39564.3 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 mPW1PW91/6-31G(2df,p)

A	B	C
0.14124	0.09663	0.06282

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

Geometric Data calculated at mPW1PW91/6-31G(2df,p)

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	-0.231	0.736	0.000
C2	0.231	-0.736	0.000
H3	-1.332	0.729	0.000
H4	1.332	-0.729	0.000
C5	0.231	1.489	1.248
C6	0.231	1.489	-1.248
C7	-0.231	-1.489	1.248
C8	-0.231	-1.489	-1.248
H9	1.324	1.467	1.334
H10	1.324	1.467	-1.334
H11	-1.324	-1.467	1.334
H12	-1.324	-1.467	-1.334
H13	-0.071	2.539	1.199
H14	-0.185	1.072	2.166
H15	-0.071	2.539	-1.199
H16	-0.185	1.072	-2.166
H17	0.071	-2.539	1.199
H18	0.185	-1.072	2.166
H19	0.071	-2.539	-1.199
H20	0.185	-1.072	-2.166

Atom - Atom Distances (Å)

	C1	C2	H3	H4	C5	C6	C7	C8	H9	H10	H11	H12	H13	H14	H15	H16	H17	H18	H19	H20
C1		1.5425	1.1001	2.1418	1.5294	1.5294	2.5509	2.5509	2.1754	2.1754	2.7970	2.7970	2.1711	2.1929	2.1711	2.1929	3.5002	2.8522	3.5002	2.8522
C2	1.5425		2.1418	1.1001	2.5509	2.5509	1.5294	1.5294	2.7970	2.7970	2.1754	2.1754	3.5002	2.8522	3.5002	2.8522	2.1711	2.1929	2.1711	2.1929
H3	1.1001	2.1418		3.0357	2.1398	2.1398	2.7723	2.7723	3.0618	3.0618	2.5688	2.5688	2.5104	2.4749	2.5104	2.4749	3.7525	3.1995	3.7525	3.1995
H4	2.1418	1.1001	3.0357		2.7723	2.7723	2.1398	2.1398	2.5688	2.5688	3.0618	3.0618	3.7525	3.1995	3.7525	3.1995	2.5104	2.4749	2.5104	2.4749
C5	1.5294	2.5509	2.1398	2.7723		2.4956	3.0142	3.9132	1.0958	2.8035	3.3411	4.2216	1.0937	1.0917	2.6792	3.4648	4.0316	2.7214	4.7155	4.2684
C6	1.5294	2.5509	2.1398	2.7723	2.4956		3.9132	3.0142	2.8035	1.0958	4.2216	3.3411	2.6792	3.4648	1.0937	1.0917	4.7155	4.2684	4.0316	2.7214
C7	2.5509	1.5294	2.7723	2.1398	3.0142	3.9132		2.4956	3.3411	4.2216	1.0958	2.8035	4.0316	2.7214	4.7155	4.2684	1.0937	1.0917	2.6792	3.4648
C8	2.5509	1.5294	2.7723	2.1398	3.9132	3.0142	2.4956		4.2216	3.3411	2.8035	1.0958	4.7155	4.2684	4.0316	2.7214	2.6792	3.4648	1.0937	1.0917
H9	2.1754	2.7970	3.0618	2.5688	1.0958	2.8035	3.3411	4.2216		2.6683	3.9512	4.7678	1.7647	1.7680	3.0839	3.8324	4.1990	2.9040	4.9018	4.4715
H10	2.1754	2.7970	3.0618	2.5688	2.8035	1.0958	4.2216	3.3411	2.6683		4.7678	3.9512	3.0839	3.8324	1.7647	1.7680	4.9018	4.4715	4.1990	2.9040
H11	2.7970	2.1754	2.5688	3.0618	3.3411	4.2216	1.0958	2.8035	3.9512	4.7678		2.6683	4.1990	2.9040	4.9018	4.4715	1.7647	1.7680	3.0839	3.8324
H12	2.7970	2.1754	2.5688	3.0618	4.2216	3.3411	2.8035	1.0958	4.7678	3.9512	2.6683		4.9018	4.4715	4.1990	2.9040	3.0839	3.8324	1.7647	1.7680
H13	2.1711	3.5002	2.5104	3.7525	1.0937	2.6792	4.0316	4.7155	1.7647	3.0839	4.1990	4.9018		1.7612	2.3970	3.6726	5.0799	3.7473	5.6170	4.9425
H14	2.1929	2.8522	2.4749	3.1995	1.0917	3.4648	2.7214	4.2684	1.7680	3.8324	2.9040	4.4715	1.7612		3.6726	4.3329	3.7473	2.1759	4.9425	4.8485
H15	2.1711	3.5002	2.5104	3.7525	2.6792	1.0937	4.7155	4.0316	3.0839	1.7647	4.9018	4.1990	2.3970	3.6726		1.7612	5.6170	4.9425	5.0799	3.7473
H16	2.1929	2.8522	2.4749	3.1995	3.4648	1.0917	4.2684	2.7214	3.8324	1.7680	4.4715	2.9040	3.6726	4.3329	1.7612		4.9425	4.8485	3.7473	2.1759
H17	3.5002	2.1711	3.7525	2.5104	4.0316	4.7155	1.0937	2.6792	4.1990	4.9018	1.7647	3.0839	5.0799	3.7473	5.6170	4.9425		1.7612	2.3970	3.6726
H18	2.8522	2.1929	3.1995	2.4749	2.7214	4.2684	1.0917	3.4648	2.9040	4.4715	1.7680	3.8324	3.7473	2.1759	4.9425	4.8485	1.7612		3.6726	4.3329
H19	3.5002	2.1711	3.7525	2.5104	4.7155	4.0316	2.6792	1.0937	4.9018	4.1990	3.0839	1.7647	5.6170	4.9425	5.0799	3.7473	2.3970	3.6726		1.7612
H20	2.8522	2.1929	3.1995	2.4749	4.2684	2.7214	3.4648	1.0917	4.4715	2.9040	3.8324	1.7680	4.9425	4.8485	3.7473	2.1759	3.6726	4.3329	1.7612

picture of Butane, 2,3-dimethyl- state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H4	107.093	C1	C2	C7	112.278
C1	C2	C8	112.278	C1	C5	H9	110.846
C1	C5	H13	110.626	C1	C5	H14	112.498
C1	C6	H10	110.846	C1	C6	H15	110.626
C1	C6	H16	112.498	C2	C1	H3	107.093
C2	C1	C5	112.278	C2	C1	C6	112.278
C2	C7	H11	110.846	C2	C7	H17	110.626
C2	C7	H18	112.498	C2	C8	H12	110.846
C2	C8	H19	110.626	C2	C8	H20	112.498
H3	C1	C5	107.813	H3	C1	C6	107.813
H4	C2	C7	107.813	H4	C2	C8	107.813
C5	C1	C6	109.347	C7	C2	C8	109.347
H9	C5	H13	107.417	H9	C5	H14	107.848
H10	C6	H15	107.417	H10	C6	H16	107.848
H11	C7	H17	107.417	H11	C7	H18	107.848
H12	C8	H19	107.417	H12	C8	H20	107.848
H13	C5	H14	107.395	H15	C6	H16	107.395
H17	C7	H18	107.395	H19	C8	H20	107.395

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/6-31G(2df,p) Charges (e)

Number	Element	Mulliken
1	C	-0.005
2	C	-0.005
3	H	0.102
4	H	0.102
5	C	-0.461
6	C	-0.461
7	C	-0.461
8	C	-0.461
9	H	0.136
10	H	0.136
11	H	0.136
12	H	0.136
13	H	0.136
14	H	0.140
15	H	0.136
16	H	0.140
17	H	0.136
18	H	0.140
19	H	0.136
20	H	0.140

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

	x	y	z	Total
	0.000	0.000	0.000	0.000
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-40.646	-0.361	0.000
y	-0.361	-41.245	0.000
z	0.000	0.000	-41.650

Traceless
	x	y	z
x	0.802	-0.361	0.000
y	-0.361	-0.097	0.000
z	0.000	0.000	-0.705

Polar
3z²-r²	-1.409
x²-y²	0.599
xy	-0.361
xz	0.000
yz	0.000

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

	x	y	z
x	8.727	0.221	0.000
y	0.221	10.692	0.000
z	0.000	0.000	10.126

<r²> (average value of r²) Å²

<r²>	207.137
(<r²>)^1/2	14.392

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)

using model chemistry: mPW1PW91/6-31G(2df,p)

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 C6H14 (Butane, 2,3-dimethyl-)

using model chemistry: mPW1PW91/6-31G(2df,p)

States and conformations

All results from a given calculation for C₆H₁₄ (Butane, 2,3-dimethyl-)