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-121G

	hartrees
Energy at 0K	-60.949398
Energy at 298.15K
HF Energy	-60.949398
Nuclear repulsion energy	71.951880

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-121G

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	3252	2967	0.00	214.89	0.08	0.15
2	A_g	1658	1513	0.00	16.73	0.75	0.85
3	A_g	1567	1430	0.00	4.65	0.72	0.83
4	A_g	1183	1079	0.00	14.57	0.53	0.69
5	A_g	1072	979	0.00	16.95	0.38	0.55
6	A_g	470	429	0.00	4.26	0.43	0.61
7	A_u	3347	3054	58.01	0.00	0.00	0.00
8	A_u	1308	1194	9.26	0.00	0.00	0.00
9	A_u	894	816	0.07	0.00	0.00	0.00
10	A_u	115	105	28.11	0.00	0.00	0.00
11	B_g	3322	3031	0.00	107.46	0.75	0.86
12	B_g	1398	1275	0.00	16.62	0.75	0.86
13	B_g	1250	1140	0.00	8.85	0.75	0.86
14	B_u	3252	2967	58.57	0.00	0.00	0.00
15	B_u	1661	1515	6.13	0.00	0.00	0.00
16	B_u	1468	1339	15.57	0.00	0.00	0.00
17	B_u	1080	986	258.92	0.00	0.00	0.00
18	B_u	297	271	37.53	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 14295.1 cm^-1
Scaled (by 0.9125) Zero Point Vibrational Energy (zpe) 13044.3 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-121G

A	B	C
1.04157	0.12587	0.11727

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

Geometric Data calculated at HF/CEP-121G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.439	0.622	0.000
C2	-0.439	-0.622	0.000
F3	-0.439	1.748	0.000
F4	0.439	-1.748	0.000
H5	1.050	0.687	0.888
H6	1.050	0.687	-0.888
H7	-1.050	-0.687	0.888
H8	-1.050	-0.687	-0.888

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5236	1.4280	2.3708	1.0799	1.0799	2.1726	2.1726
C2	1.5236		2.3708	1.4280	2.1726	2.1726	1.0799	1.0799
F3	1.4280	2.3708		3.6054	2.0330	2.0330	2.6631	2.6631
F4	2.3708	1.4280	3.6054		2.6631	2.6631	2.0330	2.0330
H5	1.0799	2.1726	2.0330	2.6631		1.7768	2.5088	3.0743
H6	1.0799	2.1726	2.0330	2.6631	1.7768		3.0743	2.5088
H7	2.1726	1.0799	2.6631	2.0330	2.5088	3.0743		1.7768
H8	2.1726	1.0799	2.6631	2.0330	3.0743	2.5088	1.7768

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	106.836	C1	C2	H7	111.998
C1	C2	H8	111.998	C2	C1	F3	106.836
C2	C1	H5	111.998	C2	C1	H6	111.998
F3	C1	H5	107.506	F3	C1	H6	107.506
F4	C2	H7	107.506	F4	C2	H8	107.506
H5	C1	H6	110.712	H7	C2	H8	110.712

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-121G Charges (e)

Number	Element	Mulliken
1	C	0.060
2	C	0.060
3	F	-0.373
4	F	-0.373
5	H	0.157
6	H	0.157
7	H	0.157
8	H	0.157

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	-21.962	4.838	0.000
y	4.838	-32.866	0.000
z	0.000	0.000	-21.167

Traceless
	x	y	z
x	5.055	4.838	0.000
y	4.838	-11.302	0.000
z	0.000	0.000	6.247

Polar
3z²-r²	12.494
x²-y²	10.904
xy	4.838
xz	0.000
yz	0.000

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

	x	y	z
x	3.279	-0.194	0.000
y	-0.194	3.359	0.000
z	0.000	0.000	3.038

<r²> (average value of r²) Å²

<r²>	75.412
(<r²>)^1/2	8.684

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at HF/CEP-121G

	hartrees
Energy at 0K	-60.948771
Energy at 298.15K
HF Energy	-60.948771
Nuclear repulsion energy	73.054096

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-121G

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	3314	3024	20.13	84.42	0.73	0.84
2	A	3243	2959	39.87	185.26	0.02	0.04
3	A	1631	1489	2.72	2.94	0.69	0.82
4	A	1557	1421	14.84	2.30	0.64	0.78
5	A	1382	1261	3.66	21.98	0.73	0.84
6	A	1213	1107	7.87	4.69	0.39	0.56
7	A	1171	1068	69.88	7.62	0.61	0.76
8	A	915	835	51.87	10.40	0.12	0.21
9	A	343	313	0.58	0.57	0.33	0.49
10	A	138	126	9.49	0.18	0.67	0.80
11	B	3324	3033	36.80	12.68	0.75	0.86
12	B	3227	2945	15.25	38.75	0.75	0.86
13	B	1629	1487	8.71	13.72	0.75	0.86
14	B	1523	1390	13.90	1.44	0.75	0.86
15	B	1333	1216	7.37	6.42	0.75	0.86
16	B	1140	1040	39.38	4.71	0.75	0.86
17	B	963	879	81.63	7.59	0.75	0.86
18	B	511	467	29.81	0.78	0.75	0.86

Unscaled Zero Point Vibrational Energy (zpe) 14278.8 cm^-1
Scaled (by 0.9125) Zero Point Vibrational Energy (zpe) 13029.4 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 HF/CEP-121G

A	B	C
0.57135	0.15975	0.14175

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

Geometric Data calculated at HF/CEP-121G

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.293	0.698	0.513
C2	-0.293	-0.698	0.513
F3	-0.293	1.459	-0.540
F4	0.293	-1.459	-0.540
H5	0.059	1.213	1.436
H6	1.359	0.682	0.342
H7	-0.059	-1.213	1.436
H8	-1.359	-0.682	0.342

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5138	1.4245	2.4003	1.0824	1.0803	2.1513	2.1588
C2	1.5138		2.4003	1.4245	2.1513	2.1588	1.0824	1.0803
F3	1.4245	2.4003		2.9763	2.0217	2.0272	3.3314	2.5489
F4	2.4003	1.4245	2.9763		3.3314	2.5489	2.0217	2.0272
H5	1.0824	2.1513	2.0217	3.3314		1.7802	2.4289	2.6072
H6	1.0803	2.1588	2.0272	2.5489	1.7802		2.6072	3.0408
H7	2.1513	1.0824	3.3314	2.0217	2.4289	2.6072		1.7802
H8	2.1588	1.0803	2.5489	2.0272	2.6072	3.0408	1.7802

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	109.512	C1	C2	H7	110.820
C1	C2	H8	111.553	C2	C1	F3	109.512
C2	C1	H5	110.820	C2	C1	H6	111.553
F3	C1	H5	106.706	F3	C1	H6	107.262
F4	C2	H7	106.706	F4	C2	H8	107.262
H5	C1	H6	110.800	H7	C2	H8	110.800

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/CEP-121G Charges (e)

Number	Element	Mulliken
1	C	0.053
2	C	0.053
3	F	-0.364
4	F	-0.364
5	H	0.144
6	H	0.167
7	H	0.144
8	H	0.167

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	3.919	3.919
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.442	2.791	0.000
y	2.791	-28.291	0.000
z	0.000	0.000	-22.495

Traceless
	x	y	z
x	3.951	2.791	0.000
y	2.791	-6.323	0.000
z	0.000	0.000	2.372

Polar
3z²-r²	4.744
x²-y²	6.849
xy	2.791
xz	0.000
yz	0.000

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

	x	y	z
x	3.145	-0.089	0.000
y	-0.089	3.250	0.000
z	0.000	0.000	3.321

<r²> (average value of r²) Å²

<r²>	68.737
(<r²>)^1/2	8.291

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

using model chemistry: HF/CEP-121G

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

using model chemistry: HF/CEP-121G

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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