CCCBDB calculation results Page

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

Conformer 1 (C2H anti)

Jump to S1C2

Energy calculated at HF/CEP-31G*

	hartrees
Energy at 0K	-61.028344
Energy at 298.15K
HF Energy	-61.028344
Nuclear repulsion energy	73.047679

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)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A_g	3293	2957	0.00	228.40	0.09	0.17
2	A_g	1662	1493	0.00	15.25	0.67	0.80
3	A_g	1602	1438	0.00	2.85	0.64	0.78
4	A_g	1183	1063	0.00	14.70	0.75	0.86
5	A_g	1159	1040	0.00	10.98	0.18	0.31
6	A_g	491	441	0.00	2.99	0.45	0.62
7	A_u	3367	3023	122.33	0.00	0.00	0.00
8	A_u	1342	1205	9.65	0.00	0.00	0.00
9	A_u	868	779	0.76	0.00	0.00	0.00
10	A_u	134	120	18.70	0.00	0.00	0.00
11	B_g	3341	3000	0.00	112.55	0.75	0.86
12	B_g	1398	1255	0.00	21.08	0.75	0.86
13	B_g	1276	1146	0.00	2.99	0.75	0.86
14	B_u	3294	2958	113.77	0.00	0.00	0.00
15	B_u	1659	1489	4.17	0.00	0.00	0.00
16	B_u	1477	1327	33.03	0.00	0.00	0.00
17	B_u	1175	1055	312.91	0.00	0.00	0.00
18	B_u	305	274	25.34	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 14511.8 cm^-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 13031.6 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
1.06238	0.13011	0.12123

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

Geometric Data calculated at HF/CEP-31G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.427	0.634	0.000
C2	-0.427	-0.634	0.000
F3	-0.427	1.715	0.000
F4	0.427	-1.715	0.000
H5	1.050	0.688	0.890
H6	1.050	0.688	-0.890
H7	-1.050	-0.688	0.890
H8	-1.050	-0.688	-0.890

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5284	1.3777	2.3489	1.0875	1.0875	2.1724	2.1724
C2	1.5284		2.3489	1.3777	2.1724	2.1724	1.0875	1.0875
F3	1.3777	2.3489		3.5347	2.0067	2.0067	2.6371	2.6371
F4	2.3489	1.3777	3.5347		2.6371	2.6371	2.0067	2.0067
H5	1.0875	2.1724	2.0067	2.6371		1.7798	2.5101	3.0770
H6	1.0875	2.1724	2.0067	2.6371	1.7798		3.0770	2.5101
H7	2.1724	1.0875	2.6371	2.0067	2.5101	3.0770		1.7798
H8	2.1724	1.0875	2.6371	2.0067	3.0770	2.5101	1.7798

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	107.741	C1	C2	H7	111.174
C1	C2	H8	111.174	C2	C1	F3	107.741
C2	C1	H5	111.174	C2	C1	H6	111.174
F3	C1	H5	108.411	F3	C1	H6	108.411
F4	C2	H7	108.411	F4	C2	H8	108.411
H5	C1	H6	109.827	H7	C2	H8	109.827

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.049
2	C	0.049
3	F	-0.312
4	F	-0.312
5	H	0.131
6	H	0.131
7	H	0.131
8	H	0.131

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	-21.763	3.468	0.000
y	3.468	-30.066	0.000
z	0.000	0.000	-21.093

Traceless
	x	y	z
x	3.816	3.468	0.000
y	3.468	-8.638	0.000
z	0.000	0.000	4.821

Polar
3z²-r²	9.643
x²-y²	8.302
xy	3.468
xz	0.000
yz	0.000

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

	x	y	z
x	3.198	0.012	0.000
y	0.012	3.267	0.000
z	0.000	0.000	2.930

<r²> (average value of r²) Å²

<r²>	73.051
(<r²>)^1/2	8.547

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at HF/CEP-31G*

	hartrees
Energy at 0K	-61.028108
Energy at 298.15K
HF Energy	-61.028108
Nuclear repulsion energy	74.206760

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)	Raman Act (Å⁴/u)	Dep P	Dep U
1	A	3335	2994	39.64	93.48	0.73	0.84
2	A	3285	2950	75.71	198.90	0.03	0.06
3	A	1639	1472	1.65	3.18	0.48	0.65
4	A	1595	1432	26.02	1.11	0.32	0.48
5	A	1405	1262	4.56	20.04	0.72	0.84
6	A	1231	1105	58.41	3.16	0.15	0.27
7	A	1222	1097	68.26	7.44	0.73	0.85
8	A	941	845	37.06	7.92	0.21	0.35
9	A	341	306	0.15	0.41	0.37	0.54
10	A	153	138	5.29	0.06	0.73	0.84
11	B	3347	3006	95.29	13.19	0.75	0.86
12	B	3271	2937	27.58	42.49	0.75	0.86
13	B	1628	1462	5.78	11.80	0.75	0.86
14	B	1531	1374	26.43	0.96	0.75	0.86
15	B	1366	1227	9.85	5.51	0.75	0.86
16	B	1195	1073	68.28	4.86	0.75	0.86
17	B	987	886	61.81	4.24	0.75	0.86
18	B	530	476	21.29	0.59	0.75	0.86

Unscaled Zero Point Vibrational Energy (zpe) 14498.9 cm^-1
Scaled (by 0.898) Zero Point Vibrational Energy (zpe) 13020.0 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 HF/CEP-31G*

A	B	C
0.58375	0.16734	0.14674

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

Geometric Data calculated at HF/CEP-31G*

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.267	0.712	0.508
C2	-0.267	-0.712	0.508
F3	-0.267	1.419	-0.543
F4	0.267	-1.419	-0.543
H5	-0.020	1.215	1.432
H6	1.350	0.718	0.403
H7	0.020	-1.215	1.432
H8	-1.350	-0.718	0.403

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5206	1.3748	2.3754	1.0900	1.0879	2.1506	2.1616
C2	1.5206		2.3754	1.3748	2.1506	2.1616	1.0900	1.0879
F3	1.3748	2.3754		2.8870	2.0001	2.0002	3.3037	2.5756
F4	2.3754	1.3748	2.8870		3.3037	2.5756	2.0001	2.0002
H5	1.0900	2.1506	2.0001	3.3037		1.7837	2.4298	2.5620
H6	1.0879	2.1616	2.0002	2.5756	1.7837		2.5620	3.0587
H7	2.1506	1.0900	3.3037	2.0001	2.4298	2.5620		1.7837
H8	2.1616	1.0879	2.5756	2.0002	2.5620	3.0587	1.7837

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	110.156	C1	C2	H7	109.834
C1	C2	H8	110.836	C2	C1	F3	110.156
C2	C1	H5	109.834	C2	C1	H6	110.836
F3	C1	H5	107.923	F3	C1	H6	108.056
F4	C2	H7	107.923	F4	C2	H8	108.056
H5	C1	H6	109.972	H7	C2	H8	109.972

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.049
2	C	0.049
3	F	-0.304
4	F	-0.304
5	H	0.119
6	H	0.136
7	H	0.119
8	H	0.136

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	3.133	3.133
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.324	1.843	0.000
y	1.843	-26.569	0.000
z	0.000	0.000	-22.044

Traceless
	x	y	z
x	2.983	1.843	0.000
y	1.843	-4.886	0.000
z	0.000	0.000	1.903

Polar
3z²-r²	3.806
x²-y²	5.246
xy	1.843
xz	0.000
yz	0.000

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

	x	y	z
x	3.039	0.043	0.000
y	0.043	3.262	0.000
z	0.000	0.000	3.114

<r²> (average value of r²) Å²

<r²>	66.601
(<r²>)^1/2	8.161

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

using model chemistry: HF/CEP-31G*

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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

using model chemistry: HF/CEP-31G*

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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