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 mPW1PW91/daug-cc-pVTZ

	hartrees
Energy at 0K	-278.335376
Energy at 298.15K
HF Energy	-278.335376
Nuclear repulsion energy	126.004222

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 mPW1PW91/daug-cc-pVTZ

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	3068	3068	0.00	251.80	0.05	0.10
2	A_g	1514	1514	0.00	7.50	0.72	0.84
3	A_g	1449	1449	0.00	1.84	0.43	0.60
4	A_g	1097	1097	0.00	6.55	0.56	0.72
5	A_g	1084	1084	0.00	8.67	0.29	0.45
6	A_g	462	462	0.00	2.50	0.35	0.52
7	A_u	3139	3139	39.64	0.00	0.00	0.00
8	A_u	1239	1239	4.48	0.00	0.00	0.00
9	A_u	814	814	0.06	0.00	0.00	0.00
10	A_u	114	114	12.45	0.00	0.00	0.00
11	B_g	3112	3112	0.00	107.63	0.75	0.86
12	B_g	1305	1305	0.00	6.74	0.75	0.86
13	B_g	1177	1177	0.00	1.12	0.75	0.86
14	B_u	3074	3074	55.62	0.00	0.00	0.00
15	B_u	1524	1524	5.04	0.00	0.00	0.00
16	B_u	1361	1361	5.87	0.00	0.00	0.00
17	B_u	1094	1094	219.88	0.00	0.00	0.00
18	B_u	281	281	18.47	0.00	0.00	0.00

Unscaled Zero Point Vibrational Energy (zpe) 13453.1 cm^-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 13453.1 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 mPW1PW91/daug-cc-pVTZ

A	B	C
1.07694	0.12969	0.12107

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

Geometric Data calculated at mPW1PW91/daug-cc-pVTZ

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.422	0.627	0.000
C2	-0.422	-0.627	0.000
F3	-0.422	1.721	0.000
F4	0.422	-1.721	0.000
H5	1.050	0.673	0.890
H6	1.050	0.673	-0.890
H7	-1.050	-0.673	0.890
H8	-1.050	-0.673	-0.890

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5116	1.3818	2.3474	1.0906	1.0906	2.1566	2.1566
C2	1.5116		2.3474	1.3818	2.1566	2.1566	1.0906	1.0906
F3	1.3818	2.3474		3.5433	2.0147	2.0147	2.6299	2.6299
F4	2.3474	1.3818	3.5433		2.6299	2.6299	2.0147	2.0147
H5	1.0906	2.1566	2.0147	2.6299		1.7806	2.4950	3.0652
H6	1.0906	2.1566	2.0147	2.6299	1.7806		3.0652	2.4950
H7	2.1566	1.0906	2.6299	2.0147	2.4950	3.0652		1.7806
H8	2.1566	1.0906	2.6299	2.0147	3.0652	2.4950	1.7806

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	108.364	C1	C2	H7	110.909
C1	C2	H8	110.909	C2	C1	F3	108.364
C2	C1	H5	110.909	C2	C1	H6	110.909
F3	C1	H5	108.577	F3	C1	H6	108.577
F4	C2	H7	108.577	F4	C2	H8	108.577
H5	C1	H6	109.439	H7	C2	H8	109.439

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/daug-cc-pVTZ Charges (e)

Number	Element	Mulliken
1	C	0.270
2	C	0.270
3	F	-0.914
4	F	-0.914
5	H	0.322
6	H	0.322
7	H	0.322
8	H	0.322

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	-22.183	3.121	0.000
y	3.121	-29.215	0.000
z	0.000	0.000	-21.518

Traceless
	x	y	z
x	3.183	3.121	0.000
y	3.121	-7.365	0.000
z	0.000	0.000	4.181

Polar
3z²-r²	8.363
x²-y²	7.032
xy	3.121
xz	0.000
yz	0.000

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

	x	y	z
x	4.397	-0.040	0.000
y	-0.040	4.612	0.000
z	0.000	0.000	4.038

<r²> (average value of r²) Å²

<r²>	87.927
(<r²>)^1/2	9.377

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at mPW1PW91/daug-cc-pVTZ

	hartrees
Energy at 0K	-278.337189
Energy at 298.15K
HF Energy	-278.337189
Nuclear repulsion energy	128.010998

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 mPW1PW91/daug-cc-pVTZ

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	3108	3108	13.05	84.23	0.74	0.85
2	A	3063	3063	36.07	235.94	0.02	0.03
3	A	1487	1487	0.84	1.44	0.65	0.79
4	A	1439	1439	11.10	1.18	0.25	0.40
5	A	1310	1310	3.51	8.05	0.65	0.79
6	A	1135	1135	63.16	2.93	0.25	0.39
7	A	1130	1130	35.04	1.66	0.66	0.80
8	A	879	879	20.89	5.82	0.15	0.27
9	A	325	325	0.46	0.42	0.28	0.44
10	A	151	151	3.61	0.12	0.75	0.86
11	B	3122	3122	30.46	11.52	0.75	0.86
12	B	3053	3053	8.34	31.90	0.75	0.86
13	B	1487	1487	10.65	6.51	0.75	0.86
14	B	1401	1401	6.44	0.01	0.75	0.86
15	B	1267	1267	7.41	2.01	0.75	0.86
16	B	1104	1104	62.06	3.75	0.75	0.86
17	B	912	912	40.97	2.20	0.75	0.86
18	B	500	500	15.68	0.45	0.75	0.86

Unscaled Zero Point Vibrational Energy (zpe) 13435.9 cm^-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 13435.9 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 mPW1PW91/daug-cc-pVTZ

A	B	C
0.58767	0.16646	0.14607

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

Geometric Data calculated at mPW1PW91/daug-cc-pVTZ

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.265	0.701	0.505
C2	-0.265	-0.701	0.505
F3	-0.265	1.429	-0.541
F4	0.265	-1.429	-0.541
H5	-0.013	1.195	1.439
H6	1.351	0.702	0.402
H7	0.013	-1.195	1.439
H8	-1.351	-0.702	0.402

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.4984	1.3803	2.3728	1.0928	1.0912	2.1285	2.1425
C2	1.4984		2.3728	1.3803	2.1285	2.1425	1.0928	1.0912
F3	1.3803	2.3728		2.9065	2.0100	2.0072	3.2991	2.5713
F4	2.3728	1.3803	2.9065		3.2991	2.5713	2.0100	2.0072
H5	1.0928	2.1285	2.0100	3.2991		1.7832	2.3902	2.5429
H6	1.0912	2.1425	2.0072	2.5713	1.7832		2.5429	3.0455
H7	2.1285	1.0928	3.2991	2.0100	2.3902	2.5429		1.7832
H8	2.1425	1.0912	2.5713	2.0072	2.5429	3.0455	1.7832

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	110.967	C1	C2	H7	109.462
C1	C2	H8	110.673	C2	C1	F3	110.967
C2	C1	H5	109.462	C2	C1	H6	110.673
F3	C1	H5	108.173	F3	C1	H6	108.045
F4	C2	H7	108.173	F4	C2	H8	108.045
H5	C1	H6	109.466	H7	C2	H8	109.466

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/daug-cc-pVTZ Charges (e)

Number	Element	Mulliken
1	C	0.196
2	C	0.196
3	F	-0.881
4	F	-0.881
5	H	0.426
6	H	0.260
7	H	0.426
8	H	0.260

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	2.676	2.676
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.751	1.698	0.000
y	1.698	-26.227	0.000
z	0.000	0.000	-22.461

Traceless
	x	y	z
x	2.592	1.698	0.000
y	1.698	-4.121	0.000
z	0.000	0.000	1.528

Polar
3z²-r²	3.057
x²-y²	4.476
xy	1.698
xz	0.000
yz	0.000

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

	x	y	z
x	4.191	0.047	0.000
y	0.047	4.578	0.000
z	0.000	0.000	4.366

<r²> (average value of r²) Å²

<r²>	79.708
(<r²>)^1/2	8.928

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

using model chemistry: mPW1PW91/daug-cc-pVTZ

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: mPW1PW91/daug-cc-pVTZ

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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