CCCBDB calculation results Page

State	Conformation	minimum conformation	conformer description	state description
1	1	no	C2H anti	¹A_g
1	2	yes	C2 gauche	¹A

Conformer 1 (C2H anti)

Jump to S1C2

Energy calculated at HF/aug-cc-pVQZ

	hartrees
Energy at 0K	-277.058852
Energy at 298.15K
HF Energy	-277.058852
Nuclear repulsion energy	127.225154

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/aug-cc-pVQZ

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_g	3207	2914	0.00	237.53	0.06	0.10
2	A_g	1647	1496	0.00	6.03	0.75	0.86
3	A_g	1590	1444	0.00	2.47	0.31	0.47
4	A_g	1178	1070	0.00	9.05	0.73	0.84
5	A_g	1154	1048	0.00	8.43	0.14	0.25
6	A_g	497	451	0.00	2.31	0.32	0.49
7	A_u	3273	2973	64.10	0.00	0.00	0.00
8	A_u	1351	1228	8.36	0.00	0.00	0.00
9	A_u	874	794	0.08	0.00	0.00	0.00
10	A_u	137	124	15.36	0.00	0.00	0.00
11	B_g	3244	2947	0.00	100.15	0.75	0.86
12	B_g	1411	1281	0.00	6.47	0.75	0.86
13	B_g	1284	1167	0.00	0.96	0.75	0.86
14	B_u	3211	2917	70.92	0.00	0.75	0.86
15	B_u	1653	1502	4.25	0.00	0.00	0.00
16	B_u	1484	1348	14.10	0.00	0.00	0.00
17	B_u	1176	1068	283.00	0.00	0.00	0.00
18	B_u	312	283	22.54	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 14340.0 cm^-1
Scaled (by 0.9085) Zero Point Vibrational Energy (zpe) 13027.9 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/aug-cc-pVQZ

A	B	C
1.08984	0.13230	0.12339

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

Geometric Data calculated at HF/aug-cc-pVQZ

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.419	0.629	0.000
C2	-0.419	-0.629	0.000
F3	-0.419	1.701	0.000
F4	0.419	-1.701	0.000
H5	1.042	0.677	0.882
H6	1.042	0.677	-0.882
H7	-1.042	-0.677	0.882
H8	-1.042	-0.677	-0.882

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5116	1.3618	2.3301	1.0806	1.0806	2.1494	2.1494
C2	1.5116		2.3301	1.3618	2.1494	2.1494	1.0806	1.0806
F3	1.3618	2.3301		3.5047	1.9906	1.9906	2.6123	2.6123
F4	2.3301	1.3618	3.5047		2.6123	2.6123	1.9906	1.9906
H5	1.0806	2.1494	1.9906	2.6123		1.7636	2.4860	3.0480
H6	1.0806	2.1494	1.9906	2.6123	1.7636		3.0480	2.4860
H7	2.1494	1.0806	2.6123	1.9906	2.4860	3.0480		1.7636
H8	2.1494	1.0806	2.6123	1.9906	3.0480	2.4860	1.7636

picture of 1,2-difluoroethane state 1 conformation 1

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	F4	108.262	C1	C2	H7	110.936
C1	C2	H8	110.936	C2	C1	F3	108.262
C2	C1	H5	110.936	C2	C1	H6	110.936
F3	C1	H5	108.633	F3	C1	H6	108.633
F4	C2	H7	108.633	F4	C2	H8	108.633
H5	C1	H6	109.374	H7	C2	H8	109.374

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/aug-cc-pVQZ Charges (e)

Number	Element	Mulliken
1	C	0.067
2	C	0.067
3	F	-0.701
4	F	-0.701
5	H	0.317
6	H	0.317
7	H	0.317
8	H	0.317

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	-22.037	3.415	0.000
y	3.415	-29.577	0.000
z	0.000	0.000	-21.307

Traceless
	x	y	z
x	3.405	3.415	0.000
y	3.415	-7.905	0.000
z	0.000	0.000	4.499

Polar
3z²-r²	8.998
x²-y²	7.540
xy	3.415
xz	0.000
yz	0.000

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

	x	y	z
x	3.982	-0.012	0.000
y	-0.012	4.116	0.000
z	0.000	0.000	3.709

<r²> (average value of r²) Å²

<r²>	86.601
(<r²>)^1/2	9.306

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at HF/aug-cc-pVQZ

	hartrees
Energy at 0K	-277.059424
Energy at 298.15K
HF Energy	-277.059424
Nuclear repulsion energy	129.321883

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/aug-cc-pVQZ

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	3240	2944	21.95	76.57	0.75	0.85
2	A	3203	2910	45.36	217.39	0.02	0.04
3	A	1624	1475	0.69	1.14	0.75	0.86
4	A	1580	1435	14.53	1.40	0.06	0.11
5	A	1417	1287	5.68	7.17	0.66	0.80
6	A	1235	1122	35.76	1.88	0.09	0.16
7	A	1216	1105	88.06	3.59	0.74	0.85
8	A	939	853	28.02	7.28	0.14	0.24
9	A	347	315	0.28	0.30	0.27	0.42
10	A	160	146	4.34	0.07	0.75	0.86
11	B	3255	2957	52.44	10.04	0.75	0.86
12	B	3189	2897	12.24	31.76	0.75	0.86
13	B	1621	1473	7.55	5.30	0.75	0.86
14	B	1533	1393	11.81	0.01	0.75	0.86
15	B	1378	1252	10.77	1.95	0.75	0.86
16	B	1197	1087	63.99	3.69	0.75	0.86
17	B	989	899	55.59	2.29	0.75	0.86
18	B	543	493	20.45	0.37	0.75	0.86

Unscaled Zero Point Vibrational Energy (zpe) 14332.6 cm^-1
Scaled (by 0.9085) Zero Point Vibrational Energy (zpe) 13021.2 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 HF/aug-cc-pVQZ

A	B	C
0.59516	0.17081	0.14942

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

Geometric Data calculated at HF/aug-cc-pVQZ

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.260	0.705	0.503
C2	-0.260	-0.705	0.503
F3	-0.260	1.405	-0.540
F4	0.260	-1.405	-0.540
H5	-0.031	1.199	1.422
H6	1.337	0.714	0.413
H7	0.031	-1.199	1.422
H8	-1.337	-0.714	0.413

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5022	1.3598	2.3539	1.0826	1.0812	2.1257	2.1383
C2	1.5022		2.3539	1.3598	2.1257	2.1383	1.0826	1.0812
F3	1.3598	2.3539		2.8585	1.9855	1.9840	3.2731	2.5615
F4	2.3539	1.3598	2.8585		3.2731	2.5615	1.9855	1.9840
H5	1.0826	2.1257	1.9855	3.2731		1.7675	2.3982	2.5264
H6	1.0812	2.1383	1.9840	2.5615	1.7675		2.5264	3.0320
H7	2.1257	1.0826	3.2731	1.9855	2.3982	2.5264		1.7675
H8	2.1383	1.0812	2.5615	1.9840	2.5264	3.0320	1.7675

picture of 1,2-difluoroethane state 1 conformation 2

More geometry information
Calculated Bond Angles

atom1	atom2	atom3	angle	atom1	atom2	atom3	angle
C1	C2	F4	110.564	C1	C2	H7	109.581
C1	C2	H8	110.670	C2	C1	F3	110.564
C2	C1	H5	109.581	C2	C1	H6	110.670
F3	C1	H5	108.231	F3	C1	H6	108.197
F4	C2	H7	108.231	F4	C2	H8	108.197
H5	C1	H6	109.549	H7	C2	H8	109.549

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/aug-cc-pVQZ Charges (e)

Number	Element	Mulliken
1	C	0.065
2	C	0.065
3	F	-0.685
4	F	-0.685
5	H	0.314
6	H	0.306
7	H	0.314
8	H	0.306

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	2.881	2.881
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.567	1.798	0.000
y	1.798	-26.223	0.000
z	0.000	0.000	-22.419

Traceless
	x	y	z
x	2.754	1.798	0.000
y	1.798	-4.230	0.000
z	0.000	0.000	1.476

Polar
3z²-r²	2.953
x²-y²	4.656
xy	1.798
xz	0.000
yz	0.000

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

	x	y	z
x	3.818	0.037	0.000
y	0.037	4.081	0.000
z	0.000	0.000	3.941

<r²> (average value of r²) Å²

<r²>	78.296
(<r²>)^1/2	8.848

All results from a given calculation for C₂H₄F₂ (1,2-difluoroethane)

using model chemistry: HF/aug-cc-pVQZ

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

	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 C2H4F2 (1,2-difluoroethane)

using model chemistry: HF/aug-cc-pVQZ

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

All results from a given calculation for C₂H₄F₂ (1,2-difluoroethane)