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 B3PW91/3-21G

	hartrees
Energy at 0K	-79.373135
Energy at 298.15K	-79.379070
HF Energy	-79.373135
Nuclear repulsion energy	42.019232

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 B3PW91/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_1g	3055	2937	0.00
2	A_1g	1455	1398	0.00
3	A_1g	991	952	0.00
4	A_1u	307	295	0.00
5	A_2u	3056	2937	45.73
6	A_2u	1462	1405	9.89
7	E_g	3110	2990	0.00
7	E_g	3110	2990	0.00
8	E_g	1567	1506	0.00
8	E_g	1567	1506	0.00
9	E_g	1252	1203	0.00
9	E_g	1252	1203	0.00
10	E_u	3138	3016	53.79
10	E_u	3138	3016	53.80
11	E_u	1567	1506	14.05
11	E_u	1567	1506	14.05
12	E_u	861	828	10.40
12	E_u	861	828	10.40

Unscaled Zero Point Vibrational Energy (zpe) 16656.9 cm^-1
Scaled (by 0.9612) Zero Point Vibrational Energy (zpe) 16010.6 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 B3PW91/3-21G

A	B	C
2.65656	0.66005	0.66005

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

Geometric Data calculated at B3PW91/3-21G

Point Group is D_3d

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.770
C2	0.000	0.000	-0.770
H3	0.000	1.024	1.161
H4	-0.887	-0.512	1.161
H5	0.887	-0.512	1.161
H6	0.000	-1.024	-1.161
H7	-0.887	0.512	-1.161
H8	0.887	0.512	-1.161

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5395	1.0965	1.0965	1.0965	2.1854	2.1854	2.1854
C2	1.5395		2.1854	2.1854	2.1854	1.0965	1.0965	1.0965
H3	1.0965	2.1854		1.7743	1.7743	3.0962	2.5374	2.5374
H4	1.0965	2.1854	1.7743		1.7743	2.5374	2.5374	3.0962
H5	1.0965	2.1854	1.7743	1.7743		2.5374	3.0962	2.5374
H6	2.1854	1.0965	3.0962	2.5374	2.5374		1.7743	1.7743
H7	2.1854	1.0965	2.5374	2.5374	3.0962	1.7743		1.7743
H8	2.1854	1.0965	2.5374	3.0962	2.5374	1.7743	1.7743

picture of Ethane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	110.888	C1	C2	H7	110.888
C1	C2	H8	110.888	C2	C1	H3	110.888
C2	C1	H4	110.888	C2	C1	H5	110.888
H3	C1	H4	108.018	H3	C1	H5	108.018
H4	C1	H5	108.018	H6	C2	H7	108.018
H6	C2	H8	108.018	H7	C2	H8	108.018

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3PW91/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.629
2	C	-0.629
3	H	0.210
4	H	0.210
5	H	0.210
6	H	0.210
7	H	0.210
8	H	0.210

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	-14.688	0.000	0.000
y	0.000	-14.688	0.000
z	0.000	0.000	-15.075

Traceless
	x	y	z
x	0.194	0.000	0.000
y	0.000	0.194	0.000
z	0.000	0.000	-0.387

Polar
3z²-r²	-0.775
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	3.144	0.000	0.000
y	0.000	3.144	0.000
z	0.000	0.000	3.354

<r²> (average value of r²) Å²

<r²>	30.745
(<r²>)^1/2	5.545

Conformer 2 (D3H)

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Energy calculated at B3PW91/3-21G

	hartrees
Energy at 0K	-79.368810
Energy at 298.15K
HF Energy	-79.368810
Nuclear repulsion energy	41.857536

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 B3PW91/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁'	3071	2952	0.00
2	A₁'	1481	1424	0.00
3	A₁'	982	944	0.00
4	A₁"	298i	287i	0.00
5	A₂"	3063	2945	47.57
6	A₂"	1461	1404	9.91
7	E'	3144	3022	44.81
7	E'	3144	3022	44.81
8	E'	1578	1516	16.04
8	E'	1578	1516	16.04
9	E'	939	902	10.24
9	E'	939	902	10.24
10	E"	3121	3000	0.00
10	E"	3121	3000	0.00
11	E"	1566	1505	0.00
11	E"	1566	1505	0.00
12	E"	1205	1159	0.00
12	E"	1205	1159	0.00

Unscaled Zero Point Vibrational Energy (zpe) 16432.6 cm^-1
Scaled (by 0.9612) Zero Point Vibrational Energy (zpe) 15795.0 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 B3PW91/3-21G

A	B	C
2.67737	0.64902	0.64902

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

Geometric Data calculated at B3PW91/3-21G

Point Group is D_3h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.777
C2	0.000	0.000	-0.777
H3	0.000	1.020	1.175
H4	-0.884	-0.510	1.175
H5	0.884	-0.510	1.175
H6	0.000	1.020	-1.175
H7	0.884	-0.510	-1.175
H8	-0.884	-0.510	-1.175

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5534	1.0954	1.0954	1.0954	2.2023	2.2023	2.2023
C2	1.5534		2.2023	2.2023	2.2023	1.0954	1.0954	1.0954
H3	1.0954	2.2023		1.7674	1.7674	2.3499	2.9404	2.9404
H4	1.0954	2.2023	1.7674		1.7674	2.9404	2.9404	2.3499
H5	1.0954	2.2023	1.7674	1.7674		2.9404	2.3499	2.9404
H6	2.2023	1.0954	2.3499	2.9404	2.9404		1.7674	1.7674
H7	2.2023	1.0954	2.9404	2.9404	2.3499	1.7674		1.7674
H8	2.2023	1.0954	2.9404	2.3499	2.9404	1.7674	1.7674

picture of Ethane state 1 conformation 2

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	111.320	C1	C2	H7	111.320
C1	C2	H8	111.320	C2	C1	H3	111.320
C2	C1	H4	111.320	C2	C1	H5	111.320
H3	C1	H4	107.561	H3	C1	H5	107.561
H4	C1	H5	107.561	H6	C2	H7	107.561
H6	C2	H8	107.561	H7	C2	H8	107.561

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3PW91/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.638
2	C	-0.638
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	-14.674	0.000	0.000
y	0.000	-14.674	0.000
z	0.000	0.000	-14.972

Traceless
	x	y	z
x	0.149	0.000	0.000
y	0.000	0.149	0.000
z	0.000	0.000	-0.298

Polar
3z²-r²	-0.597
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	3.073	0.000	0.000
y	0.000	3.073	0.000
z	0.000	0.000	3.301

<r²> (average value of r²) Å²

<r²>	30.997
(<r²>)^1/2	5.567

All results from a given calculation for C₂H₆ (Ethane)

using model chemistry: B3PW91/3-21G

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: B3PW91/3-21G

States and conformations

Conformer 1 (D3D)

Conformer 2 (D3H)

All results from a given calculation for C₂H₆ (Ethane)