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/cc-pVTZ

	hartrees
Energy at 0K	-278.328407
Energy at 298.15K
HF Energy	-278.328407
Nuclear repulsion energy	126.160412

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/cc-pVTZ

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3064	2939	0.00
2	A_g	1517	1455	0.00
3	A_g	1457	1397	0.00
4	A_g	1102	1057	0.00
5	A_g	1092	1048	0.00
6	A_g	464	445	0.00
7	A_u	3136	3008	50.26
8	A_u	1242	1191	4.11
9	A_u	816	782	0.01
10	A_u	113	109	12.09
11	B_g	3108	2981	0.00
12	B_g	1307	1254	0.00
13	B_g	1182	1133	0.00
14	B_u	3071	2946	59.37
15	B_u	1528	1466	3.41
16	B_u	1366	1311	6.81
17	B_u	1108	1062	207.53
18	B_u	279	267	17.75

Unscaled Zero Point Vibrational Energy (zpe) 13476.0 cm^-1
Scaled (by 0.9592) Zero Point Vibrational Energy (zpe) 12926.2 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 mPW1PW91/cc-pVTZ

A	B	C
1.07916	0.13002	0.12137

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

Geometric Data calculated at mPW1PW91/cc-pVTZ

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.421	0.627	0.000
C2	-0.421	-0.627	0.000
F3	-0.421	1.718	0.000
F4	0.421	-1.718	0.000
H5	1.052	0.669	0.890
H6	1.052	0.669	-0.890
H7	-1.052	-0.669	0.890
H8	-1.052	-0.669	-0.890

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5111	1.3784	2.3456	1.0911	1.0911	2.1542	2.1542
C2	1.5111		2.3456	1.3784	2.1542	2.1542	1.0911	1.0911
F3	1.3784	2.3456		3.5384	2.0153	2.0153	2.6245	2.6245
F4	2.3456	1.3784	3.5384		2.6245	2.6245	2.0153	2.0153
H5	1.0911	2.1542	2.0153	2.6245		1.7791	2.4926	3.0624
H6	1.0911	2.1542	2.0153	2.6245	1.7791		3.0624	2.4926
H7	2.1542	1.0911	2.6245	2.0153	2.4926	3.0624		1.7791
H8	2.1542	1.0911	2.6245	2.0153	3.0624	2.4926	1.7791

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	108.452	C1	C2	H7	110.717
C1	C2	H8	110.717	C2	C1	F3	108.452
C2	C1	H5	110.717	C2	C1	H6	110.717
F3	C1	H5	108.838	F3	C1	H6	108.838
F4	C2	H7	108.838	F4	C2	H8	108.838
H5	C1	H6	109.234	H7	C2	H8	109.234

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.124
2	C	0.124
3	F	-0.236
4	F	-0.236
5	H	0.056
6	H	0.056
7	H	0.056
8	H	0.056

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	-21.908	2.795	0.000
y	2.795	-28.676	0.000
z	0.000	0.000	-21.409

Traceless
	x	y	z
x	3.134	2.795	0.000
y	2.795	-7.017	0.000
z	0.000	0.000	3.883

Polar
3z²-r²	7.766
x²-y²	6.768
xy	2.795
xz	0.000
yz	0.000

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

	x	y	z
x	3.954	0.016	0.000
y	0.016	4.051	0.000
z	0.000	0.000	3.656

<r²> (average value of r²) Å²

<r²>	87.559
(<r²>)^1/2	9.357

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at mPW1PW91/cc-pVTZ

	hartrees
Energy at 0K	-278.329961
Energy at 298.15K
HF Energy	-278.329961
Nuclear repulsion energy	128.158736

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/cc-pVTZ

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3105	2979	16.76
2	A	3060	2935	36.02
3	A	1491	1430	0.24
4	A	1443	1385	12.72
5	A	1313	1259	2.94
6	A	1143	1096	81.12
7	A	1133	1087	13.19
8	A	883	847	20.89
9	A	324	311	0.35
10	A	149	143	3.52
11	B	3119	2992	37.23
12	B	3050	2926	10.00
13	B	1489	1428	9.16
14	B	1408	1350	6.88
15	B	1271	1219	7.08
16	B	1112	1067	56.56
17	B	916	878	38.82
18	B	498	477	15.15

Unscaled Zero Point Vibrational Energy (zpe) 13452.8 cm^-1
Scaled (by 0.9592) Zero Point Vibrational Energy (zpe) 12903.9 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/cc-pVTZ

A	B	C
0.58876	0.16692	0.14648

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

Geometric Data calculated at mPW1PW91/cc-pVTZ

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.265	0.701	0.504
C2	-0.265	-0.701	0.504
F3	-0.265	1.427	-0.541
F4	0.265	-1.427	-0.541
H5	-0.010	1.193	1.440
H6	1.351	0.698	0.402
H7	0.010	-1.193	1.440
H8	-1.351	-0.698	0.402

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.4982	1.3774	2.3699	1.0932	1.0916	2.1282	2.1398
C2	1.4982		2.3699	1.3774	2.1282	2.1398	1.0932	1.0916
F3	1.3774	2.3699		2.9019	2.0106	2.0078	3.2959	2.5662
F4	2.3699	1.3774	2.9019		3.2959	2.5662	2.0106	2.0078
H5	1.0932	2.1282	2.0106	3.2959		1.7824	2.3867	2.5403
H6	1.0916	2.1398	2.0078	2.5662	1.7824		2.5403	3.0423
H7	2.1282	1.0932	3.2959	2.0106	2.3867	2.5403		1.7824
H8	2.1398	1.0916	2.5662	2.0078	2.5403	3.0423	1.7824

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	110.935	C1	C2	H7	109.428
C1	C2	H8	110.451	C2	C1	F3	110.935
C2	C1	H5	109.428	C2	C1	H6	110.451
F3	C1	H5	108.390	F3	C1	H6	108.260
F4	C2	H7	108.390	F4	C2	H8	108.260
H5	C1	H6	109.331	H7	C2	H8	109.331

Electronic energy levels

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

Number	Element	Mulliken
1	C	0.138
2	C	0.138
3	F	-0.233
4	F	-0.233
5	H	0.040
6	H	0.055
7	H	0.040
8	H	0.055

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	2.553	2.553
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.566	1.549	0.000
y	1.549	-25.874	0.000
z	0.000	0.000	-22.166

Traceless
	x	y	z
x	2.454	1.549	0.000
y	1.549	-4.008	0.000
z	0.000	0.000	1.554

Polar
3z²-r²	3.108
x²-y²	4.308
xy	1.549
xz	0.000
yz	0.000

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

	x	y	z
x	3.789	0.067	0.000
y	0.067	4.076	0.000
z	0.000	0.000	3.896

<r²> (average value of r²) Å²

<r²>	79.373
(<r²>)^1/2	8.909

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

using model chemistry: mPW1PW91/cc-pVTZ

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: mPW1PW91/cc-pVTZ

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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