CCCBDB calculation results Page

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

Energy calculated at MP2=FULL/3-21G*

	hartrees
Energy at 0K	-234.637838
Energy at 298.15K	-234.653143
HF Energy	-234.068136
Nuclear repulsion energy	260.838756

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=FULL/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3174	3009	0.00
2	A_g	3144	2980	0.00
3	A_g	3077	2917	0.00
4	A_g	3052	2893	0.00
5	A_g	1624	1540	0.00
6	A_g	1602	1518	0.00
7	A_g	1502	1424	0.00
8	A_g	1424	1350	0.00
9	A_g	1268	1202	0.00
10	A_g	1242	1177	0.00
11	A_g	961	911	0.00
12	A_g	765	725	0.00
13	A_g	509	483	0.00
14	A_g	402	381	0.00
15	A_g	246	233	0.00
16	A_u	3173	3008	48.71
17	A_u	3138	2974	0.01
18	A_u	3074	2914	26.77
19	A_u	1609	1525	5.23
20	A_u	1585	1503	1.54
21	A_u	1481	1404	11.68
22	A_u	1400	1327	2.74
23	A_u	1098	1041	2.77
24	A_u	1011	959	0.27
25	A_u	979	928	3.29
26	A_u	323	306	0.00
27	A_u	212	201	0.03
28	A_u	60	57	0.00
29	B_g	3158	2994	0.00
30	B_g	3138	2975	0.00
31	B_g	3072	2913	0.00
32	B_g	1594	1511	0.00
33	B_g	1589	1507	0.00
34	B_g	1473	1396	0.00
35	B_g	1414	1340	0.00
36	B_g	1202	1139	0.00
37	B_g	995	944	0.00
38	B_g	971	920	0.00
39	B_g	443	420	0.00
40	B_g	224	213	0.00
41	B_u	3161	2997	60.38
42	B_u	3146	2982	113.74
43	B_u	3075	2916	52.95
44	B_u	3066	2907	12.80
45	B_u	1609	1526	19.36
46	B_u	1602	1519	14.62
47	B_u	1491	1413	15.93
48	B_u	1374	1303	3.82
49	B_u	1227	1163	8.00
50	B_u	1061	1006	10.27
51	B_u	867	822	2.28
52	B_u	422	400	0.27
53	B_u	356	338	0.19
54	B_u	232	220	0.01

Unscaled Zero Point Vibrational Energy (zpe) 42547.5 cm^-1
Scaled (by 0.948) Zero Point Vibrational Energy (zpe) 40335.0 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=FULL/3-21G*

A	B	C
0.13880	0.09492	0.06179

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

Geometric Data calculated at MP2=FULL/3-21G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.779	0.000
C2	0.000	-0.779	0.000
H3	-1.051	1.107	0.000
H4	1.051	-1.107	0.000
C5	0.699	1.353	1.261
C6	0.699	1.353	-1.261
C7	-0.699	-1.353	1.261
C8	-0.699	-1.353	-1.261
H9	1.728	0.978	1.316
H10	1.728	0.978	-1.316
H11	-1.728	-0.978	1.316
H12	-1.728	-0.978	-1.316
H13	0.733	2.448	1.205
H14	0.174	1.076	2.180
H15	0.733	2.448	-1.205
H16	0.174	1.076	-2.180
H17	-0.733	-2.448	1.205
H18	-0.174	-1.076	2.180
H19	-0.733	-2.448	-1.205
H20	-0.174	-1.076	-2.180

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		1.5572	1.1007	2.1584	1.5522	1.5522	2.5738	2.5738	2.1813	2.1813	2.7937	2.7937	2.1854	2.2070	2.1854	2.2070	3.5213	2.8673	3.5213	2.8673
C2	1.5572		2.1584	1.1007	2.5738	2.5738	1.5522	1.5522	2.7937	2.7937	2.1813	2.1813	3.5213	2.8673	3.5213	2.8673	2.1854	2.2070	2.1854	2.2070
H3	1.1007	2.1584		3.0521	2.1705	2.1705	2.7870	2.7870	3.0773	3.0773	2.5569	2.5569	2.5361	2.5008	2.5361	2.5008	3.7668	3.2068	3.7668	3.2068
H4	2.1584	1.1007	3.0521		2.7870	2.7870	2.1705	2.1705	2.5569	2.5569	3.0773	3.0773	3.7668	3.2068	3.7668	3.2068	2.5361	2.5008	2.5361	2.5008
C5	1.5522	2.5738	2.1705	2.7870		2.5224	3.0462	3.9550	1.0973	2.8002	3.3660	4.2388	1.0964	1.0936	2.6985	3.4919	4.0623	2.7400	4.7521	4.3018
C6	1.5522	2.5738	2.1705	2.7870	2.5224		3.9550	3.0462	2.8002	1.0973	4.2388	3.3660	2.6985	3.4919	1.0964	1.0936	4.7521	4.3018	4.0623	2.7400
C7	2.5738	1.5522	2.7870	2.1705	3.0462	3.9550		2.5224	3.3660	4.2388	1.0973	2.8002	4.0623	2.7400	4.7521	4.3018	1.0964	1.0936	2.6985	3.4919
C8	2.5738	1.5522	2.7870	2.1705	3.9550	3.0462	2.5224		4.2388	3.3660	2.8002	1.0973	4.7521	4.3018	4.0623	2.7400	2.6985	3.4919	1.0964	1.0936
H9	2.1813	2.7937	3.0773	2.5569	1.0973	2.8002	3.3660	4.2388		2.6313	3.9720	4.7645	1.7784	1.7808	3.0830	3.8266	4.2200	2.9304	4.9144	4.4787
H10	2.1813	2.7937	3.0773	2.5569	2.8002	1.0973	4.2388	3.3660	2.6313		4.7645	3.9720	3.0830	3.8266	1.7784	1.7808	4.9144	4.4787	4.2200	2.9304
H11	2.7937	2.1813	2.5569	3.0773	3.3660	4.2388	1.0973	2.8002	3.9720	4.7645		2.6313	4.2200	2.9304	4.9144	4.4787	1.7784	1.7808	3.0830	3.8266
H12	2.7937	2.1813	2.5569	3.0773	4.2388	3.3660	2.8002	1.0973	4.7645	3.9720	2.6313		4.9144	4.4787	4.2200	2.9304	3.0830	3.8266	1.7784	1.7808
H13	2.1854	3.5213	2.5361	3.7668	1.0964	2.6985	4.0623	4.7521	1.7784	3.0830	4.2200	4.9144		1.7733	2.4104	3.6951	5.1104	3.7669	5.6504	4.9698
H14	2.2070	2.8673	2.5008	3.2068	1.0936	3.4919	2.7400	4.3018	1.7808	3.8266	2.9304	4.4787	1.7733		3.6951	4.3599	3.7669	2.1797	4.9698	4.8744
H15	2.1854	3.5213	2.5361	3.7668	2.6985	1.0964	4.7521	4.0623	3.0830	1.7784	4.9144	4.2200	2.4104	3.6951		1.7733	5.6504	4.9698	5.1104	3.7669
H16	2.2070	2.8673	2.5008	3.2068	3.4919	1.0936	4.3018	2.7400	3.8266	1.7808	4.4787	2.9304	3.6951	4.3599	1.7733		4.9698	4.8744	3.7669	2.1797
H17	3.5213	2.1854	3.7668	2.5361	4.0623	4.7521	1.0964	2.6985	4.2200	4.9144	1.7784	3.0830	5.1104	3.7669	5.6504	4.9698		1.7733	2.4104	3.6951
H18	2.8673	2.2070	3.2068	2.5008	2.7400	4.3018	1.0936	3.4919	2.9304	4.4787	1.7808	3.8266	3.7669	2.1797	4.9698	4.8744	1.7733		3.6951	4.3599
H19	3.5213	2.1854	3.7668	2.5361	4.7521	4.0623	2.6985	1.0964	4.9144	4.2200	3.0830	1.7784	5.6504	4.9698	5.1104	3.7669	2.4104	3.6951		1.7733
H20	2.8673	2.2070	3.2068	2.5008	4.3018	2.7400	3.4919	1.0936	4.4787	2.9304	3.8266	1.7808	4.9698	4.8744	3.7669	2.1797	3.6951	4.3599	1.7733

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	107.349	C1	C2	C7	111.738
C1	C2	C8	111.738	C1	C5	H9	109.637
C1	C5	H13	110.015	C1	C5	H14	111.893
C1	C6	H10	109.637	C1	C6	H15	110.015
C1	C6	H16	111.893	C2	C1	H3	107.349
C2	C1	C5	111.738	C2	C1	C6	111.738
C2	C7	H11	109.637	C2	C7	H17	110.015
C2	C7	H18	111.893	C2	C8	H12	109.637
C2	C8	H19	110.015	C2	C8	H20	111.893
H3	C1	C5	108.613	H3	C1	C6	108.613
H4	C2	C7	108.613	H4	C2	C8	108.613
C5	C1	C6	108.693	C7	C2	C8	108.693
H9	C5	H13	108.327	H9	C5	H14	108.744
H10	C6	H15	108.327	H10	C6	H16	108.744
H11	C7	H17	108.327	H11	C7	H18	108.744
H12	C8	H19	108.327	H12	C8	H20	108.744
H13	C5	H14	108.141	H15	C6	H16	108.141
H17	C7	H18	108.141	H19	C8	H20	108.141

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability

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

using model chemistry: MP2=FULL/3-21G*

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: MP2=FULL/3-21G*

States and conformations

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