CCCBDB calculation results Page

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

Energy calculated at mPW1PW91/6-31G**

	hartrees
Energy at 0K	-237.042063
Energy at 298.15K	-237.057161
Nuclear repulsion energy	262.864470

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**

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3165	3011	0.00
2	A_g	3139	2987	0.00
3	A_g	3065	2917	0.00
4	A_g	3022	2875	0.00
5	A_g	1541	1466	0.00
6	A_g	1520	1446	0.00
7	A_g	1435	1366	0.00
8	A_g	1394	1326	0.00
9	A_g	1225	1166	0.00
10	A_g	1204	1146	0.00
11	A_g	966	919	0.00
12	A_g	769	732	0.00
13	A_g	499	475	0.00
14	A_g	391	372	0.00
15	A_g	243	231	0.00
16	A_u	3164	3011	55.25
17	A_u	3134	2982	1.13
18	A_u	3060	2912	46.13
19	A_u	1521	1447	5.33
20	A_u	1496	1424	1.15
21	A_u	1417	1349	11.50
22	A_u	1348	1282	2.79
23	A_u	1105	1052	1.51
24	A_u	980	933	0.69
25	A_u	933	888	2.91
26	A_u	313	298	0.02
27	A_u	199	190	0.03
28	A_u	61	58	0.00
29	B_g	3153	3000	0.00
30	B_g	3134	2982	0.00
31	B_g	3060	2911	0.00
32	B_g	1506	1433	0.00
33	B_g	1499	1427	0.00
34	B_g	1415	1346	0.00
35	B_g	1362	1296	0.00
36	B_g	1191	1134	0.00
37	B_g	972	924	0.00
38	B_g	925	880	0.00
39	B_g	429	408	0.00
40	B_g	205	195	0.00
41	B_u	3156	3003	71.04
42	B_u	3140	2988	128.60
43	B_u	3063	2915	64.46
44	B_u	3036	2889	35.16
45	B_u	1526	1452	17.00
46	B_u	1516	1442	18.18
47	B_u	1428	1359	15.04
48	B_u	1313	1249	6.09
49	B_u	1187	1130	8.30
50	B_u	1007	958	8.04
51	B_u	890	847	2.83
52	B_u	406	387	0.13
53	B_u	350	333	0.13
54	B_u	221	210	0.03

Unscaled Zero Point Vibrational Energy (zpe) 41699.2 cm^-1
Scaled (by 0.9515) Zero Point Vibrational Energy (zpe) 39676.8 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**

A	B	C
0.14114	0.09657	0.06278

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

Geometric Data calculated at mPW1PW91/6-31G**

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.772	0.000
C2	0.000	-0.772	0.000
H3	-1.052	1.094	0.000
H4	1.052	-1.094	0.000
C5	0.669	1.351	1.248
C6	0.669	1.351	-1.248
C7	-0.669	-1.351	1.248
C8	-0.669	-1.351	-1.248
H9	1.703	0.999	1.334
H10	1.703	0.999	-1.334
H11	-1.703	-0.999	1.334
H12	-1.703	-0.999	-1.334
H13	0.697	2.443	1.199
H14	0.146	1.080	2.167
H15	0.697	2.443	-1.199
H16	0.146	1.080	-2.167
H17	-0.697	-2.443	1.199
H18	-0.146	-1.080	2.167
H19	-0.697	-2.443	-1.199
H20	-0.146	-1.080	-2.167

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		1.5439	1.1005	2.1425	1.5299	1.5299	2.5520	2.5520	2.1753	2.1753	2.7958	2.7958	2.1721	2.1940	2.1721	2.1940	3.5018	2.8546	3.5018	2.8546
C2	1.5439		2.1425	1.1005	2.5520	2.5520	1.5299	1.5299	2.7958	2.7958	2.1753	2.1753	3.5018	2.8546	3.5018	2.8546	2.1721	2.1940	2.1721	2.1940
H3	1.1005	2.1425		3.0363	2.1414	2.1414	2.7723	2.7723	3.0626	3.0626	2.5664	2.5664	2.5137	2.4765	2.5137	2.4765	3.7523	3.2011	3.7523	3.2011
H4	2.1425	1.1005	3.0363		2.7723	2.7723	2.1414	2.1414	2.5664	2.5664	3.0626	3.0626	3.7523	3.2011	3.7523	3.2011	2.5137	2.4765	2.5137	2.4765
C5	1.5299	2.5520	2.1414	2.7723		2.4963	3.0151	3.9144	1.0958	2.8040	3.3400	4.2210	1.0937	1.0918	2.6802	3.4660	4.0332	2.7238	4.7174	4.2708
C6	1.5299	2.5520	2.1414	2.7723	2.4963		3.9144	3.0151	2.8040	1.0958	4.2210	3.3400	2.6802	3.4660	1.0937	1.0918	4.7174	4.2708	4.0332	2.7238
C7	2.5520	1.5299	2.7723	2.1414	3.0151	3.9144		2.4963	3.3400	4.2210	1.0958	2.8040	4.0332	2.7238	4.7174	4.2708	1.0937	1.0918	2.6802	3.4660
C8	2.5520	1.5299	2.7723	2.1414	3.9144	3.0151	2.4963		4.2210	3.3400	2.8040	1.0958	4.7174	4.2708	4.0332	2.7238	2.6802	3.4660	1.0937	1.0918
H9	2.1753	2.7958	3.0626	2.5664	1.0958	2.8040	3.3400	4.2210		2.6687	3.9486	4.7658	1.7650	1.7677	3.0848	3.8331	4.1987	2.9041	4.9021	4.4724
H10	2.1753	2.7958	3.0626	2.5664	2.8040	1.0958	4.2210	3.3400	2.6687		4.7658	3.9486	3.0848	3.8331	1.7650	1.7677	4.9021	4.4724	4.1987	2.9041
H11	2.7958	2.1753	2.5664	3.0626	3.3400	4.2210	1.0958	2.8040	3.9486	4.7658		2.6687	4.1987	2.9041	4.9021	4.4724	1.7650	1.7677	3.0848	3.8331
H12	2.7958	2.1753	2.5664	3.0626	4.2210	3.3400	2.8040	1.0958	4.7658	3.9486	2.6687		4.9021	4.4724	4.1987	2.9041	3.0848	3.8331	1.7650	1.7677
H13	2.1721	3.5018	2.5137	3.7523	1.0937	2.6802	4.0332	4.7174	1.7650	3.0848	4.1987	4.9021		1.7607	2.3986	3.6739	5.0818	3.7499	5.6194	4.9456
H14	2.1940	2.8546	2.4765	3.2011	1.0918	3.4660	2.7238	4.2708	1.7677	3.8331	2.9041	4.4724	1.7607		3.6739	4.3348	3.7499	2.1796	4.9456	4.8519
H15	2.1721	3.5018	2.5137	3.7523	2.6802	1.0937	4.7174	4.0332	3.0848	1.7650	4.9021	4.1987	2.3986	3.6739		1.7607	5.6194	4.9456	5.0818	3.7499
H16	2.1940	2.8546	2.4765	3.2011	3.4660	1.0918	4.2708	2.7238	3.8331	1.7677	4.4724	2.9041	3.6739	4.3348	1.7607		4.9456	4.8519	3.7499	2.1796
H17	3.5018	2.1721	3.7523	2.5137	4.0332	4.7174	1.0937	2.6802	4.1987	4.9021	1.7650	3.0848	5.0818	3.7499	5.6194	4.9456		1.7607	2.3986	3.6739
H18	2.8546	2.1940	3.2011	2.4765	2.7238	4.2708	1.0918	3.4660	2.9041	4.4724	1.7677	3.8331	3.7499	2.1796	4.9456	4.8519	1.7607		3.6739	4.3348
H19	3.5018	2.1721	3.7523	2.5137	4.7174	4.0332	2.6802	1.0937	4.9021	4.1987	3.0848	1.7650	5.6194	4.9456	5.0818	3.7499	2.3986	3.6739		1.7607
H20	2.8546	2.1940	3.2011	2.4765	4.2708	2.7238	3.4660	1.0918	4.4724	2.9041	3.8331	1.7677	4.9456	4.8519	3.7499	2.1796	3.6739	4.3348	1.7607

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	107.040	C1	C2	C7	112.244
C1	C2	C8	112.244	C1	C5	H9	110.799
C1	C5	H13	110.673	C1	C5	H14	112.552
C1	C6	H10	110.799	C1	C6	H15	110.673
C1	C6	H16	112.552	C2	C1	H3	107.040
C2	C1	C5	112.244	C2	C1	C6	112.244
C2	C7	H11	110.799	C2	C7	H17	110.673
C2	C7	H18	112.552	C2	C8	H12	110.799
C2	C8	H19	110.673	C2	C8	H20	112.552
H3	C1	C5	107.881	H3	C1	C6	107.881
H4	C2	C7	107.881	H4	C2	C8	107.881
C5	C1	C6	109.341	C7	C2	C8	109.341
H9	C5	H13	107.440	H9	C5	H14	107.817
H10	C6	H15	107.440	H10	C6	H16	107.817
H11	C7	H17	107.440	H11	C7	H18	107.817
H12	C8	H19	107.440	H12	C8	H20	107.817
H13	C5	H14	107.346	H15	C6	H16	107.346
H17	C7	H18	107.346	H19	C8	H20	107.346

Electronic energy levels

Electronic state

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

Number	Element	Mulliken
1	C	-0.098
2	C	-0.098
3	H	0.115
4	H	0.115
5	C	-0.388
6	C	-0.388
7	C	-0.388
8	C	-0.388
9	H	0.125
10	H	0.125
11	H	0.125
12	H	0.125
13	H	0.125
14	H	0.129
15	H	0.125
16	H	0.129
17	H	0.125
18	H	0.129
19	H	0.125
20	H	0.129

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	-41.098	-0.347	0.000
y	-0.347	-41.085	0.000
z	0.000	0.000	-41.569

Traceless
	x	y	z
x	0.229	-0.347	0.000
y	-0.347	0.249	0.000
z	0.000	0.000	-0.478

Polar
3z²-r²	-0.956
x²-y²	-0.013
xy	-0.347
xz	0.000
yz	0.000

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

	x	y	z
x	0.000	0.000	0.000
y	0.000	0.000	0.000
z	0.000	0.000	0.000

<r²> (average value of r²) Å²

<r²>	207.292
(<r²>)^1/2	14.398

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

using model chemistry: mPW1PW91/6-31G**

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 C6H14 (Butane, 2,3-dimethyl-)

using model chemistry: mPW1PW91/6-31G**

States and conformations

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