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/cc-pVQZ

	hartrees
Energy at 0K	-277.058852
Energy at 298.15K
HF Energy	-277.058852
Nuclear repulsion energy	127.230888

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/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	2913	0.00	237.63	0.06	0.10
2	A_g	1647	1496	0.00	6.04	0.75	0.86
3	A_g	1590	1444	0.00	2.47	0.31	0.47
4	A_g	1179	1071	0.00	9.04	0.73	0.84
5	A_g	1154	1048	0.00	8.42	0.15	0.25
6	A_g	497	451	0.00	2.31	0.32	0.49
7	A_u	3272	2972	64.25	0.00	0.34	0.51
8	A_u	1351	1228	8.35	0.00	0.00	0.00
9	A_u	874	794	0.08	0.00	0.35	0.51
10	A_u	137	124	15.36	0.00	0.37	0.54
11	B_g	3243	2946	0.00	100.21	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	71.03	0.00	0.40	0.57
15	B_u	1653	1502	4.27	0.00	0.00	0.00
16	B_u	1484	1348	14.13	0.00	0.73	0.00
17	B_u	1176	1069	282.91	0.00	0.27	0.42
18	B_u	312	283	22.53	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 14340.0 cm^-1
Scaled (by 0.9084) Zero Point Vibrational Energy (zpe) 13026.5 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/cc-pVQZ

A	B	C
1.09001	0.13231	0.12340

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

Geometric Data calculated at HF/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	1.3616	2.3301	1.0807	1.0807	2.1493	2.1493
C2	1.5116		2.3301	1.3616	2.1493	2.1493	1.0807	1.0807
F3	1.3616	2.3301		3.5046	1.9907	1.9907	2.6121	2.6121
F4	2.3301	1.3616	3.5046		2.6121	2.6121	1.9907	1.9907
H5	1.0807	2.1493	1.9907	2.6121		1.7635	2.4860	3.0479
H6	1.0807	2.1493	1.9907	2.6121	1.7635		3.0479	2.4860
H7	2.1493	1.0807	2.6121	1.9907	2.4860	3.0479		1.7635
H8	2.1493	1.0807	2.6121	1.9907	3.0479	2.4860	1.7635

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	108.273	C1	C2	H7	110.925
C1	C2	H8	110.925	C2	C1	F3	108.273
C2	C1	H5	110.925	C2	C1	H6	110.925
F3	C1	H5	108.650	F3	C1	H6	108.650
F4	C2	H7	108.650	F4	C2	H8	108.650
H5	C1	H6	109.355	H7	C2	H8	109.355

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/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	3.412	0.000
y	3.412	-29.574	0.000
z	0.000	0.000	-21.309

Traceless
	x	y	z
x	3.405	3.412	0.000
y	3.412	-7.901	0.000
z	0.000	0.000	4.496

Polar
3z²-r²	8.993
x²-y²	7.537
xy	3.412
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	4.115	0.000
z	0.000	0.000	3.710

<r²> (average value of r²) Å²

<r²>	86.596
(<r²>)^1/2	9.306

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at HF/cc-pVQZ

	hartrees
Energy at 0K	-277.059425
Energy at 298.15K
HF Energy	-277.059425
Nuclear repulsion energy	129.312699

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/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	21.49	76.91	0.74	0.85
2	A	3203	2910	45.76	217.02	0.02	0.04
3	A	1624	1475	0.71	1.14	0.75	0.86
4	A	1580	1435	14.47	1.40	0.06	0.11
5	A	1417	1287	5.68	7.17	0.66	0.80
6	A	1235	1122	34.99	1.87	0.08	0.16
7	A	1216	1105	88.68	3.61	0.74	0.85
8	A	938	853	28.13	7.27	0.14	0.24
9	A	347	316	0.29	0.30	0.27	0.42
10	A	160	146	4.34	0.07	0.75	0.86
11	B	3255	2957	52.46	9.92	0.75	0.86
12	B	3189	2897	12.11	31.88	0.75	0.86
13	B	1621	1473	7.54	5.30	0.75	0.86
14	B	1533	1393	11.80	0.01	0.75	0.86
15	B	1378	1252	10.78	1.95	0.75	0.86
16	B	1196	1087	63.97	3.69	0.75	0.86
17	B	989	898	55.74	2.29	0.75	0.86
18	B	543	493	20.46	0.37	0.75	0.86

Unscaled Zero Point Vibrational Energy (zpe) 14332.3 cm^-1
Scaled (by 0.9084) Zero Point Vibrational Energy (zpe) 13019.5 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/cc-pVQZ

A	B	C
0.59527	0.17075	0.14938

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

Geometric Data calculated at HF/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	1.406	-0.539
F4	0.260	-1.406	-0.539
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		1.5021	1.3599	2.3540	1.0826	1.0811	2.1258	2.1383
C2	1.5021		2.3540	1.3599	2.1258	2.1383	1.0826	1.0811
F3	1.3599	2.3540		2.8593	1.9855	1.9838	3.2733	2.5614
F4	2.3540	1.3599	2.8593		3.2733	2.5614	1.9855	1.9838
H5	1.0826	2.1258	1.9855	3.2733		1.7676	2.3982	2.5268
H6	1.0811	2.1383	1.9838	2.5614	1.7676		2.5268	3.0319
H7	2.1258	1.0826	3.2733	1.9855	2.3982	2.5268		1.7676
H8	2.1383	1.0811	2.5614	1.9838	2.5268	3.0319	1.7676

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	110.572	C1	C2	H7	109.587
C1	C2	H8	110.679	C2	C1	F3	110.572
C2	C1	H5	109.587	C2	C1	H6	110.679
F3	C1	H5	108.220	F3	C1	H6	108.178
F4	C2	H7	108.220	F4	C2	H8	108.178
H5	C1	H6	109.554	H7	C2	H8	109.554

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.064
2	C	0.064
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	2.882	2.882
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.567	1.800	0.000
y	1.800	-26.227	0.000
z	0.000	0.000	-22.418

Traceless
	x	y	z
x	2.756	1.800	0.000
y	1.800	-4.234	0.000
z	0.000	0.000	1.479

Polar
3z²-r²	2.958
x²-y²	4.660
xy	1.800
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>	78.310
(<r²>)^1/2	8.849

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

using model chemistry: HF/cc-pVQZ

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/cc-pVQZ

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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