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 B1B95/3-21G

	hartrees
Energy at 0K	-276.678578
Energy at 298.15K
HF Energy	-276.678578
Nuclear repulsion energy	124.484013

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 B1B95/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3085	2952	0.00
2	A_g	1580	1511	0.00
3	A_g	1474	1410	0.00
4	A_g	1080	1033	0.00
5	A_g	1065	1019	0.00
6	A_g	437	418	0.00
7	A_u	3154	3017	65.70
8	A_u	1233	1179	0.56
9	A_u	858	821	0.13
10	A_u	119	114	13.71
11	B_g	3124	2989	0.00
12	B_g	1347	1289	0.00
13	B_g	1179	1128	0.00
14	B_u	3095	2961	51.41
15	B_u	1595	1526	2.05
16	B_u	1394	1334	7.97
17	B_u	1107	1059	99.83
18	B_u	226	216	19.70

Unscaled Zero Point Vibrational Energy (zpe) 13574.9 cm^-1
Scaled (by 0.9567) Zero Point Vibrational Energy (zpe) 12987.1 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 B1B95/3-21G

A	B	C
1.05039	0.12698	0.11835

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

Geometric Data calculated at B1B95/3-21G

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.433	0.624	0.000
C2	-0.433	-0.624	0.000
F3	-0.433	1.742	0.000
F4	0.433	-1.742	0.000
H5	1.068	0.633	0.889
H6	1.068	0.633	-0.889
H7	-1.068	-0.633	0.889
H8	-1.068	-0.633	-0.889

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5180	1.4139	2.3656	1.0923	1.0923	2.1491	2.1491
C2	1.5180		2.3656	1.4139	2.1491	2.1491	1.0923	1.0923
F3	1.4139	2.3656		3.5897	2.0666	2.0666	2.6138	2.6138
F4	2.3656	1.4139	3.5897		2.6138	2.6138	2.0666	2.0666
H5	1.0923	2.1491	2.0666	2.6138		1.7772	2.4822	3.0528
H6	1.0923	2.1491	2.0666	2.6138	1.7772		3.0528	2.4822
H7	2.1491	1.0923	2.6138	2.0666	2.4822	3.0528		1.7772
H8	2.1491	1.0923	2.6138	2.0666	3.0528	2.4822	1.7772

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	107.525	C1	C2	H7	109.769
C1	C2	H8	109.769	C2	C1	F3	107.525
C2	C1	H5	109.769	C2	C1	H6	109.769
F3	C1	H5	110.440	F3	C1	H6	110.440
F4	C2	H7	110.440	F4	C2	H8	110.440
H5	C1	H6	108.886	H7	C2	H8	108.886

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B1B95/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.140
2	C	-0.140
3	F	-0.303
4	F	-0.303
5	H	0.221
6	H	0.221
7	H	0.221
8	H	0.221

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	-21.403	2.792	0.000
y	2.792	-28.874	0.000
z	0.000	0.000	-21.190

Traceless
	x	y	z
x	3.629	2.792	0.000
y	2.792	-7.578	0.000
z	0.000	0.000	3.949

Polar
3z²-r²	7.897
x²-y²	7.471
xy	2.792
xz	0.000
yz	0.000

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

	x	y	z
x	3.181	-0.079	0.000
y	-0.079	3.105	0.000
z	0.000	0.000	2.978

<r²> (average value of r²) Å²

<r²>	89.097
(<r²>)^1/2	9.439

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at B1B95/3-21G

	hartrees
Energy at 0K	-276.678785
Energy at 298.15K
HF Energy	-276.678785
Nuclear repulsion energy	126.365274

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 B1B95/3-21G

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3119	2984	24.56
2	A	3079	2946	26.16
3	A	1558	1490	0.00
4	A	1457	1394	12.09
5	A	1338	1280	0.02
6	A	1138	1088	12.09
7	A	1123	1074	33.81
8	A	883	845	13.71
9	A	307	294	0.76
10	A	146	139	3.90
11	B	3134	2998	44.01
12	B	3067	2934	15.29
13	B	1560	1492	6.75
14	B	1466	1402	7.33
15	B	1275	1219	1.34
16	B	1102	1054	23.68
17	B	936	896	22.48
18	B	452	433	15.31

Unscaled Zero Point Vibrational Energy (zpe) 13568.9 cm^-1
Scaled (by 0.9567) Zero Point Vibrational Energy (zpe) 12981.3 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 B1B95/3-21G

A	B	C
0.56481	0.16319	0.14325

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

Geometric Data calculated at B1B95/3-21G

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.280	0.700	0.514
C2	-0.280	-0.700	0.514
F3	-0.280	1.444	-0.550
F4	0.280	-1.444	-0.550
H5	0.040	1.183	1.466
H6	1.366	0.650	0.399
H7	-0.040	-1.183	1.466
H8	-1.366	-0.650	0.399

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5081	1.4133	2.3935	1.0944	1.0930	2.1343	2.1317
C2	1.5081		2.3935	1.4133	2.1343	2.1317	1.0944	1.0930
F3	1.4133	2.3935		2.9421	2.0574	2.0585	3.3199	2.5425
F4	2.3935	1.4133	2.9421		3.3199	2.5425	2.0574	2.0585
H5	1.0944	2.1343	2.0574	3.3199		1.7835	2.3671	2.5445
H6	1.0930	2.1317	2.0585	2.5425	1.7835		2.5445	3.0251
H7	2.1343	1.0944	3.3199	2.0574	2.3671	2.5445		1.7835
H8	2.1317	1.0930	2.5425	2.0585	2.5445	3.0251	1.7835

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	109.989	C1	C2	H7	109.158
C1	C2	H8	109.037	C2	C1	F3	109.989
C2	C1	H5	109.158	C2	C1	H6	109.037
F3	C1	H5	109.610	F3	C1	H6	109.781
F4	C2	H7	109.610	F4	C2	H8	109.781
H5	C1	H6	109.247	H7	C2	H8	109.247

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B1B95/3-21G Charges (e)

Number	Element	Mulliken
1	C	-0.130
2	C	-0.130
3	F	-0.300
4	F	-0.300
5	H	0.203
6	H	0.227
7	H	0.203
8	H	0.227

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	2.695	2.695
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.228	1.610	0.000
y	1.610	-25.974	0.000
z	0.000	0.000	-21.795

Traceless
	x	y	z
x	2.657	1.610	0.000
y	1.610	-4.463	0.000
z	0.000	0.000	1.806

Polar
3z²-r²	3.613
x²-y²	4.747
xy	1.610
xz	0.000
yz	0.000

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

	x	y	z
x	3.058	-0.016	0.000
y	-0.016	3.156	0.000
z	0.000	0.000	3.186

<r²> (average value of r²) Å²

<r²>	80.735
(<r²>)^1/2	8.985

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

using model chemistry: B1B95/3-21G

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: B1B95/3-21G

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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