CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	yes	D3D	¹A_1g
1	2	no	D3H	¹A₁^'

Conformer 1 (D3D)

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Energy calculated at mPW1PW91/3-21G

	hartrees
Energy at 0K	-79.378062
Energy at 298.15K	-79.384007
HF Energy	-79.378062
Nuclear repulsion energy	42.085641

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 mPW1PW91/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A_1g	3073	2934	0.00	185.82	0.01	0.02
2	A_1g	1465	1398	0.00	9.10	0.72	0.84
3	A_1g	999	954	0.00	7.80	0.29	0.45
4	A_1u	309	295	0.00	0.00	0.00	0.00
5	A_2u	3074	2934	44.27	0.00	0.00	0.00
6	A_2u	1472	1405	10.85	0.00	0.00	0.00
7	E_g	3130	2988	0.00	120.25	0.75	0.86
7	E_g	3130	2988	0.00	120.25	0.75	0.86
8	E_g	1575	1504	0.00	45.76	0.75	0.86
8	E_g	1575	1504	0.00	45.76	0.75	0.86
9	E_g	1260	1203	0.00	3.32	0.75	0.86
9	E_g	1260	1203	0.00	3.32	0.75	0.86
10	E_u	3158	3014	51.09	0.00	0.00	0.00
10	E_u	3158	3014	51.09	0.00	0.00	0.00
11	E_u	1575	1503	14.63	0.00	0.00	0.00
11	E_u	1575	1503	14.63	0.00	0.00	0.00
12	E_u	867	827	10.52	0.00	0.00	0.00
12	E_u	867	827	10.52	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 16760.1 cm^-1
Scaled (by 0.9546) Zero Point Vibrational Energy (zpe) 15999.2 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 mPW1PW91/3-21G

A	B	C
2.66455	0.66218	0.66218

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

Geometric Data calculated at mPW1PW91/3-21G

Point Group is D_3d

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.769
C2	0.000	0.000	-0.769
H3	0.000	1.023	1.159
H4	-0.886	-0.511	1.159
H5	0.886	-0.511	1.159
H6	0.000	-1.023	-1.159
H7	-0.886	0.511	-1.159
H8	0.886	0.511	-1.159

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5371	1.0948	1.0948	1.0948	2.1819	2.1819	2.1819
C2	1.5371		2.1819	2.1819	2.1819	1.0948	1.0948	1.0948
H3	1.0948	2.1819		1.7717	1.7717	3.0912	2.5332	2.5332
H4	1.0948	2.1819	1.7717		1.7717	2.5332	2.5332	3.0912
H5	1.0948	2.1819	1.7717	1.7717		2.5332	3.0912	2.5332
H6	2.1819	1.0948	3.0912	2.5332	2.5332		1.7717	1.7717
H7	2.1819	1.0948	2.5332	2.5332	3.0912	1.7717		1.7717
H8	2.1819	1.0948	2.5332	3.0912	2.5332	1.7717	1.7717

picture of Ethane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	110.881	C1	C2	H7	110.881
C1	C2	H8	110.881	C2	C1	H3	110.881
C2	C1	H4	110.881	C2	C1	H5	110.881
H3	C1	H4	108.026	H3	C1	H5	108.026
H4	C1	H5	108.026	H6	C2	H7	108.026
H6	C2	H8	108.026	H7	C2	H8	108.026

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.640
2	C	-0.640
3	H	0.213
4	H	0.213
5	H	0.213
6	H	0.213
7	H	0.213
8	H	0.213

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	-14.685	0.000	0.000
y	0.000	-14.685	0.000
z	0.000	0.000	-15.078

Traceless
	x	y	z
x	0.196	0.000	0.000
y	0.000	0.196	0.000
z	0.000	0.000	-0.393

Polar
3z²-r²	-0.786
x²-y²	0.000
xy	0.000
xz	0.000
yz	0.000

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

	x	y	z
x	3.124	0.000	0.000
y	0.000	3.124	0.000
z	0.000	0.000	3.335

<r²> (average value of r²) Å²

<r²>	30.675
(<r²>)^1/2	5.538

Conformer 2 (D3H)

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Energy calculated at mPW1PW91/3-21G

	hartrees
Energy at 0K	-79.373709
Energy at 298.15K
HF Energy	-79.373709
Nuclear repulsion energy	41.924210

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 mPW1PW91/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁'	3088	2948	0.00
2	A₁'	1490	1422	0.00
3	A₁'	991	946	0.00
4	A₁"	299i	286i	0.00
5	A₂"	3081	2941	46.14
6	A₂"	1469	1402	10.84
7	E'	3163	3020	42.37
7	E'	3163	3020	42.37
8	E'	1586	1514	16.68
8	E'	1586	1514	16.68
9	E'	944	901	10.36
9	E'	944	901	10.36
10	E"	3141	2998	0.00
10	E"	3141	2998	0.00
11	E"	1574	1503	0.00
11	E"	1574	1503	0.00
12	E"	1213	1158	0.00
12	E"	1213	1158	0.00

Unscaled Zero Point Vibrational Energy (zpe) 16530.9 cm^-1
Scaled (by 0.9546) Zero Point Vibrational Energy (zpe) 15780.4 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 mPW1PW91/3-21G

A	B	C
2.68519	0.65121	0.65121

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

Geometric Data calculated at mPW1PW91/3-21G

Point Group is D_3h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.775
C2	0.000	0.000	-0.775
H3	0.000	1.019	1.173
H4	-0.882	-0.509	1.173
H5	0.882	-0.509	1.173
H6	0.000	1.019	-1.173
H7	0.882	-0.509	-1.173
H8	-0.882	-0.509	-1.173

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5507	1.0938	1.0938	1.0938	2.1987	2.1987	2.1987
C2	1.5507		2.1987	2.1987	2.1987	1.0938	1.0938	1.0938
H3	1.0938	2.1987		1.7648	1.7648	2.3460	2.9357	2.9357
H4	1.0938	2.1987	1.7648		1.7648	2.9357	2.9357	2.3460
H5	1.0938	2.1987	1.7648	1.7648		2.9357	2.3460	2.9357
H6	2.1987	1.0938	2.3460	2.9357	2.9357		1.7648	1.7648
H7	2.1987	1.0938	2.9357	2.9357	2.3460	1.7648		1.7648
H8	2.1987	1.0938	2.9357	2.3460	2.9357	1.7648	1.7648

picture of Ethane state 1 conformation 2

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	111.319	C1	C2	H7	111.319
C1	C2	H8	111.319	C2	C1	H3	111.319
C2	C1	H4	111.319	C2	C1	H5	111.319
H3	C1	H4	107.562	H3	C1	H5	107.562
H4	C1	H5	107.562	H6	C2	H7	107.562
H6	C2	H8	107.562	H7	C2	H8	107.562

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.649
2	C	-0.649
3	H	0.216
4	H	0.216
5	H	0.216
6	H	0.216
7	H	0.216
8	H	0.216

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	-14.672	0.000	0.000
y	0.000	-14.672	0.000
z	0.000	0.000	-14.973

Traceless
	x	y	z
x	0.151	0.000	0.000
y	0.000	0.151	0.000
z	0.000	0.000	-0.301

Polar
3z²-r²	-0.603
x²-y²	0.000
xy	0.000
xz	0.000
yz	0.000

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

	x	y	z
x	3.053	0.000	0.000
y	0.000	3.053	0.000
z	0.000	0.000	3.282

<r²> (average value of r²) Å²

<r²>	30.925
(<r²>)^1/2	5.561

All results from a given calculation for C₂H₆ (Ethane)

using model chemistry: mPW1PW91/3-21G

States and conformations

Conformer 1 (D3D)

Conformer 2 (D3H)

	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 C2H6 (Ethane)

using model chemistry: mPW1PW91/3-21G

States and conformations

Conformer 1 (D3D)

Conformer 2 (D3H)

All results from a given calculation for C₂H₆ (Ethane)