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)

Jump to S1C2

Energy calculated at HF/CEP-31G

	hartrees
Energy at 0K	-14.432996
Energy at 298.15K	-14.438982
HF Energy	-14.432996
Nuclear repulsion energy	26.465897

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 HF/CEP-31G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_1g	3210	2893	0.00
2	A_1g	1566	1412	0.00
3	A_1g	1069	964	0.00
4	A_1u	308	278	0.00
5	A_2u	3195	2880	116.73
6	A_2u	1548	1396	3.85
7	E_g	3262	2941	0.00
7	E_g	3262	2941	0.00
8	E_g	1636	1474	0.00
8	E_g	1636	1474	0.00
9	E_g	1334	1202	0.00
9	E_g	1334	1202	0.00
10	E_u	3291	2966	198.60
10	E_u	3291	2966	198.60
11	E_u	1638	1476	11.37
11	E_u	1638	1476	11.37
12	E_u	896	808	5.73
12	E_u	896	808	5.73

Unscaled Zero Point Vibrational Energy (zpe) 17503.4 cm^-1
Scaled (by 0.9014) Zero Point Vibrational Energy (zpe) 15777.6 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 HF/CEP-31G

A	B	C
2.68753	0.65544	0.65544

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

Geometric Data calculated at HF/CEP-31G

Point Group is D_3d

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.774
C2	0.000	0.000	-0.774
H3	0.000	1.018	1.166
H4	-0.882	-0.509	1.166
H5	0.882	-0.509	1.166
H6	0.000	-1.018	-1.166
H7	-0.882	0.509	-1.166
H8	0.882	0.509	-1.166

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5471	1.0915	1.0915	1.0915	2.1907	2.1907	2.1907
C2	1.5471		2.1907	2.1907	2.1907	1.0915	1.0915	1.0915
H3	1.0915	2.1907		1.7641	1.7641	3.0964	2.5447	2.5447
H4	1.0915	2.1907	1.7641		1.7641	2.5447	2.5447	3.0964
H5	1.0915	2.1907	1.7641	1.7641		2.5447	3.0964	2.5447
H6	2.1907	1.0915	3.0964	2.5447	2.5447		1.7641	1.7641
H7	2.1907	1.0915	2.5447	2.5447	3.0964	1.7641		1.7641
H8	2.1907	1.0915	2.5447	3.0964	2.5447	1.7641	1.7641

picture of Ethane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	111.073	C1	C2	H7	111.073
C1	C2	H8	111.073	C2	C1	H3	111.073
C2	C1	H4	111.073	C2	C1	H5	111.073
H3	C1	H4	107.823	H3	C1	H5	107.823
H4	C1	H5	107.823	H6	C2	H7	107.823
H6	C2	H8	107.823	H7	C2	H8	107.823

Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G Charges (e)

Number	Element	Mulliken
1	C	-0.294
2	C	-0.294
3	H	0.098
4	H	0.098
5	H	0.098
6	H	0.098
7	H	0.098
8	H	0.098

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	-14.765	0.000	0.000
y	0.000	-14.765	0.000
z	0.000	0.000	-15.569

Traceless
	x	y	z
x	0.402	0.000	0.000
y	0.000	0.402	0.000
z	0.000	0.000	-0.803

Polar
3z²-r²	-1.607
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	2.965	0.000	0.000
y	0.000	2.965	0.000
z	0.000	0.000	3.409

<r²> (average value of r²) Å²

<r²>	28.558
(<r²>)^1/2	5.344

Conformer 2 (D3H)

Jump to S1C1

Energy calculated at HF/CEP-31G

	hartrees
Energy at 0K	-14.428741
Energy at 298.15K
HF Energy	-14.428741
Nuclear repulsion energy	26.395928

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 HF/CEP-31G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A₁'	3221	2903	0.00
2	A₁'	1588	1432	0.00
3	A₁'	1067	962	0.00
4	A₁"	296i	266i	0.00
5	A₂"	3201	2885	128.12
6	A₂"	1549	1397	3.87
7	E'	3296	2971	177.59
7	E'	3296	2971	177.59
8	E'	1645	1483	14.25
8	E'	1645	1483	14.25
9	E'	969	873	6.37
9	E'	969	873	6.37
10	E"	3267	2945	0.00
10	E"	3267	2945	0.00
11	E"	1634	1473	0.00
11	E"	1634	1473	0.00
12	E"	1299	1171	0.00
12	E"	1299	1171	0.00

Unscaled Zero Point Vibrational Energy (zpe) 17274.0 cm^-1
Scaled (by 0.9014) Zero Point Vibrational Energy (zpe) 15570.8 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 HF/CEP-31G

A	B	C
2.70860	0.64604	0.64604

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

Geometric Data calculated at HF/CEP-31G

Point Group is D_3h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.000	0.000	0.779
C2	0.000	0.000	-0.779
H3	0.000	1.015	1.179
H4	-0.879	-0.507	1.179
H5	0.879	-0.507	1.179
H6	0.000	1.015	-1.179
H7	0.879	-0.507	-1.179
H8	-0.879	-0.507	-1.179

Atom - Atom Distances (Å)

	C1	C2	H3	H4	H5	H6	H7	H8
C1		1.5584	1.0906	1.0906	1.0906	2.2057	2.2057	2.2057
C2	1.5584		2.2057	2.2057	2.2057	1.0906	1.0906	1.0906
H3	1.0906	2.2057		1.7572	1.7572	2.3587	2.9413	2.9413
H4	1.0906	2.2057	1.7572		1.7572	2.9413	2.9413	2.3587
H5	1.0906	2.2057	1.7572	1.7572		2.9413	2.3587	2.9413
H6	2.2057	1.0906	2.3587	2.9413	2.9413		1.7572	1.7572
H7	2.2057	1.0906	2.9413	2.9413	2.3587	1.7572		1.7572
H8	2.2057	1.0906	2.9413	2.3587	2.9413	1.7572	1.7572

picture of Ethane state 1 conformation 2

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	H6	111.526	C1	C2	H7	111.526
C1	C2	H8	111.526	C2	C1	H3	111.526
C2	C1	H4	111.526	C2	C1	H5	111.526
H3	C1	H4	107.341	H3	C1	H5	107.341
H4	C1	H5	107.341	H6	C2	H7	107.341
H6	C2	H8	107.341	H7	C2	H8	107.341

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-31G Charges (e)

Number	Element	Mulliken
1	C	-0.319
2	C	-0.319
3	H	0.106
4	H	0.106
5	H	0.106
6	H	0.106
7	H	0.106
8	H	0.106

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	-14.754	0.000	0.000
y	0.000	-14.754	0.000
z	0.000	0.000	-15.569

Traceless
	x	y	z
x	0.408	0.000	0.000
y	0.000	0.408	0.000
z	0.000	0.000	-0.815

Polar
3z²-r²	-1.631
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	2.922	0.000	0.000
y	0.000	2.922	0.000
z	0.000	0.000	3.320

<r²> (average value of r²) Å²

<r²>	28.762
(<r²>)^1/2	5.363

All results from a given calculation for C₂H₆ (Ethane)

using model chemistry: HF/CEP-31G

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
	Home All data for one species Geometry Experimental Experimental Geometries Same bond/angle many molecules Internal Coordinates by type Bond angles Calculated Calculated geometry Rotational constant Moments of inertia Products of moments of inertia BSE Bond lengths Show me a calculated geometry Comparisons Bonds, angles Rotational Constants Products of moments of inertia Point group Bad Calculations Bad moment of inertia Tutorials and Explanations Angle formulas Vibrations Experimental Vibrational frequencies Calculated Frequencies Scale factors Reactions Entropies Ions List Ions Energy Calculated Ionization Energy Compare Ionzation energy Electron Affinity Calculated Electron affinity Compare Electron affinity Proton Affinity Calculated Proton affinity Compare Proton affinity Ionization changes point group Experimental One molecule all properties One property a few molecules Enthalpy of formation Entropy Integrated Heat Capacity Heat Capacity Rotational Constants Vibrational Frequencies Dipole moment Ionization Energy Polarizability Quadrupole Point Groups Geometry Experimental Geometries Internal Coordinates by type Bond angles Rotational Constants Point Groups Diatomic bond lengths Vibrations Vibrational frequencies Diatomic Triatomics Energy Atomization Energy Internal Rotation Electrostatics Dipole Quadrupole Polarizability Reference Data Reference states Spin Splittings Molecules with good enthalpy Enthalpy at 0 Kelvin Calculated Energy Optimized Energy Energy 298K Minimum conformation Hydrogen bonds H bond with counterpoise Reaction Reaction Energy 0K Reaction Energy 298K Internal Rotation Barriers to internal rotation Rotational barrier and dipole Rotational Barrier 2 molecules Orbital HOMO LUMO gap HOMO Orbital Energies Nuclear repulsion energy Correlation Full vs Frozen core energies Partial correlation energies Ion Calculated Ionization Energy Vertical ionization Energy Calculated Electron affinity Calculated Proton affinity Atom charge differences Excited State Singlet triplet gap Electronic state Transition state Basis Set Extrapolation BSE energy BSE Bond lengths Geometry Calculated geometry AIM bond orders One type of bond Rotation Rotational constant Products of moments of inertia Moments of inertia Inertial defects Second moments Point group State symmetry <r2> Sorted by r2 Z-matrix Bad Calculations Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Frequencies Animated vibrations Anharmonic Zero point energy (ZPE) Scale Factors Scale factors Scale factor uncertainty Calculate a scale factor Why scale vibrations Set scaling factors Bad Calculations Bad Vib. HF vs MP2 Bad vib. Calc. vs exp. Big anharmonicity Electrostatics Charges Mulliken CHELP Aim ESP Dipole Dipole Dipole angle Dipole calculation types Quadrupole Polarizability Spin Spin density Entropy and Heat Capacity Entropy Reaction entropy Heat Capacity Reaction Reaction Energy 0K Reaction Energy 298K Isodesmic reactions Transition State Transition state Transition state frequencies Transition state geometries IRC Lookup by property By frequency Comparisons Geometry Bonds, angles Bond, angle, or dihedral DFT grid size on point group DFT grid on bond length Core correlation - bond length Same bond/angle many molecules Isoelectronic diatomics Isoelectronic triatomic angles Average bond lengths Rotation Rotational Constants Products of moments of inertia Point group Vibrations Vibrations 2 calculations Frequency differences One frequency Zero point energy Intensity Intensity for one mode Vibrational intensities Reduced mass comparison Anharmonic Triatomic Scale factors Energy Reaction Reaction Energy 0K Reaction Energy 298K Atomization 0K Atomization 298K Single point vs optimized DFT grid size on energy Semiempirical enthalpy Internal rotation Similar molecules Conformation Sets of isomers Sets of tautomers Isomers Entropy Entropy Heat capacity Entropy of several molecules Integrated heat capacity Reaction entropy Electrostatics Dipole Polarizability Several molecules Quadrupole Ion Compare Ionzation energy Koopman ionization energy Koopman IE for a few molecules Compare Electron affinity Compare Proton affinity Protonation Site Resources Info on Results Calculations Done Method and basis set List molecules One molecule Multiple conformers, states Multiple conformers, states Basis functions used I/O files Input/output files MOL file Z-matrix wfn files Glossary Conversion Forms B to I, I to B Angle formulas Integrated heat Capacity Calculating Enthalpy Links NIST Links NIST webbook bibliographic data CCCBDB Experimental data External links Basis Set Exchange Computational Chemistry List Thermochemistry in Gaussian Minnesota Database Collection Benchmark Energy and Geometry Point Groups Thermochemistry Thermochemistry Molecules with good enthalpy A → B + C Reference states Tutorials Vibrations Why scale vibrations Zero-point energies Entropy Methyl rotor entropy Entropy and conformations Energy Getting enthalpy of formation Vertical vs adiabatic IE Thermo from calculations Electrostatics Dipole parts by point group Quadrupoles Geometry Angle formulas Cost Cost Comparison Timings Comparison Bad Calculations Geometry Bad moment of inertia Bad Calculated Bond Lengths Bad point group Worst molecules Vibrations Bad vib. Calc. vs exp. Bad Vib. HF vs MP2 Bad scale factors Low excited states Oddities NaCN Is not linear FAQ Help Units Choose Units Energy Bond length Rotational Constant Moment of Inertia Dipole and Quadrupole Polarizability Explanations Hartree cm-1 Debye Credits Just show me Show me a calculated geometry Summary Using older interface Limit Basis sets Method options List Recent molecules Choose a few Molecules Number of atoms By heavy atoms Diatomics InChI Deuterated Dimers Geometry Point group Point group count Bonds types Isodesmic reactions Bad point group Multiple conformers, states Vibrations Big anharmonicity Energy Enthalpy at 0 Kelvin Similar molecules Similar Isomers Cis/trans Tautomers Multiple conformers, states Ions, Dipoles, etc. List Ions Ionization changes point group Dipole Quadrupole Polarizability Proton Affinities Index of CCCBDB Feedback Error form Wants
You are here: Calculated > Energy > Optimized > Energy

All results from a given calculation for C2H6 (Ethane)

using model chemistry: HF/CEP-31G

States and conformations

Conformer 1 (D3D)

Conformer 2 (D3H)

All results from a given calculation for C₂H₆ (Ethane)