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 mPW1PW91/3-21G*

	hartrees
Energy at 0K	-276.701608
Energy at 298.15K
HF Energy	-276.701608
Nuclear repulsion energy	124.450328

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 mPW1PW91/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A_g	3093	2937	0.00
2	A_g	1587	1507	0.00
3	A_g	1483	1408	0.00
4	A_g	1087	1032	0.00
5	A_g	1071	1017	0.00
6	A_g	442	419	0.00
7	A_u	3161	3002	65.26
8	A_u	1242	1179	0.61
9	A_u	865	822	0.15
10	A_u	120	114	13.98
11	B_g	3132	2974	0.00
12	B_g	1358	1289	0.00
13	B_g	1186	1126	0.00
14	B_u	3102	2946	51.69
15	B_u	1603	1522	2.28
16	B_u	1404	1333	7.52
17	B_u	1112	1056	100.90
18	B_u	235	223	19.93

Unscaled Zero Point Vibrational Energy (zpe) 13640.3 cm^-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 12952.9 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 mPW1PW91/3-21G*

A	B	C
1.05133	0.12682	0.11822

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

Geometric Data calculated at mPW1PW91/3-21G*

Point Group is C_2h

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.432	0.624	0.000
C2	-0.432	-0.624	0.000
F3	-0.432	1.743	0.000
F4	0.432	-1.743	0.000
H5	1.068	0.634	0.889
H6	1.068	0.634	-0.889
H7	-1.068	-0.634	0.889
H8	-1.068	-0.634	-0.889

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5186	1.4134	2.3675	1.0928	1.0928	2.1502	2.1502
C2	1.5186		2.3675	1.4134	2.1502	2.1502	1.0928	1.0928
F3	1.4134	2.3675		3.5916	2.0662	2.0662	2.6163	2.6163
F4	2.3675	1.4134	3.5916		2.6163	2.6163	2.0662	2.0662
H5	1.0928	2.1502	2.0662	2.6163		1.7777	2.4837	3.0543
H6	1.0928	2.1502	2.0662	2.6163	1.7777		3.0543	2.4837
H7	2.1502	1.0928	2.6163	2.0662	2.4837	3.0543		1.7777
H8	2.1502	1.0928	2.6163	2.0662	3.0543	2.4837	1.7777

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	107.642	C1	C2	H7	109.770
C1	C2	H8	109.770	C2	C1	F3	107.642
C2	C1	H5	109.770	C2	C1	H6	109.770
F3	C1	H5	110.401	F3	C1	H6	110.401
F4	C2	H7	110.401	F4	C2	H8	110.401
H5	C1	H6	108.845	H7	C2	H8	108.845

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)

Number	Element	Mulliken
1	C	-0.149
2	C	-0.149
3	F	-0.307
4	F	-0.307
5	H	0.228
6	H	0.228
7	H	0.228
8	H	0.228

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	-21.410	2.827	0.000
y	2.827	-28.971	0.000
z	0.000	0.000	-21.191

Traceless
	x	y	z
x	3.671	2.827	0.000
y	2.827	-7.670	0.000
z	0.000	0.000	4.000

Polar
3z²-r²	7.999
x²-y²	7.561
xy	2.827
xz	0.000
yz	0.000

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

	x	y	z
x	3.163	-0.079	0.000
y	-0.079	3.090	0.000
z	0.000	0.000	2.966

<r²> (average value of r²) Å²

<r²>	89.196
(<r²>)^1/2	9.444

Conformer 2 (C2 gauche)

Jump to S1C1

Energy calculated at mPW1PW91/3-21G*

	hartrees
Energy at 0K	-276.701764
Energy at 298.15K
HF Energy	-276.701764
Nuclear repulsion energy	126.294811

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 mPW1PW91/3-21G*

Mode Number	Symmetry	Frequency (cm^-1)	Scaled Frequency (cm^-1)	IR Intensities (km mol^-1)
1	A	3127	2970	24.13
2	A	3088	2932	26.32
3	A	1565	1486	0.01
4	A	1465	1392	12.00
5	A	1347	1279	0.03
6	A	1143	1086	11.40
7	A	1129	1072	34.50
8	A	887	842	14.04
9	A	312	297	0.78
10	A	147	139	4.02
11	B	3142	2984	43.70
12	B	3075	2920	15.41
13	B	1567	1488	7.03
14	B	1473	1399	7.20
15	B	1282	1218	1.42
16	B	1107	1052	23.76
17	B	942	895	23.00
18	B	460	437	15.48

Unscaled Zero Point Vibrational Energy (zpe) 13628.9 cm^-1
Scaled (by 0.9496) Zero Point Vibrational Energy (zpe) 12942.0 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 mPW1PW91/3-21G*

A	B	C
0.56628	0.16258	0.14285

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

Geometric Data calculated at mPW1PW91/3-21G*

Point Group is C₂

Cartesians (Å)

Atom	x (Å)	y (Å)	z (Å)
C1	0.280	0.701	0.512
C2	-0.280	-0.701	0.512
F3	-0.280	1.448	-0.549
F4	0.280	-1.448	-0.549
H5	0.040	1.182	1.466
H6	1.366	0.652	0.397
H7	-0.040	-1.182	1.466
H8	-1.366	-0.652	0.397

Atom - Atom Distances (Å)

	C1	C2	F3	F4	H5	H6	H7	H8
C1		1.5087	1.4130	2.3961	1.0949	1.0936	2.1347	2.1330
C2	1.5087		2.3961	1.4130	2.1347	2.1330	1.0949	1.0936
F3	1.4130	2.3961		2.9487	2.0570	2.0582	3.3217	2.5461
F4	2.3961	1.4130	2.9487		3.3217	2.5461	2.0570	2.0582
H5	1.0949	2.1347	2.0570	3.3217		1.7839	2.3662	2.5459
H6	1.0936	2.1330	2.0582	2.5461	1.7839		2.5459	3.0269
H7	2.1347	1.0949	3.3217	2.0570	2.3662	2.5459		1.7839
H8	2.1330	1.0936	2.5461	2.0582	2.5459	3.0269	1.7839

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	110.146	C1	C2	H7	109.119
C1	C2	H8	109.059	C2	C1	F3	110.146
C2	C1	H5	109.119	C2	C1	H6	109.059
F3	C1	H5	109.559	F3	C1	H6	109.737
F4	C2	H7	109.559	F4	C2	H8	109.737
H5	C1	H6	109.200	H7	C2	H8	109.200

Electronic energy levels

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at mPW1PW91/3-21G* Charges (e)

Number	Element	Mulliken
1	C	-0.139
2	C	-0.139
3	F	-0.304
4	F	-0.304
5	H	0.210
6	H	0.233
7	H	0.210
8	H	0.233

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	2.719	2.719
CHELPG
AIM
ESP

Electric Quadrupole moment
Quadrupole components in D Å

Primitive
	x	y	z
x	-21.231	1.632	0.000
y	1.632	-26.050	0.000
z	0.000	0.000	-21.806

Traceless
	x	y	z
x	2.697	1.632	0.000
y	1.632	-4.532	0.000
z	0.000	0.000	1.835

Polar
3z²-r²	3.670
x²-y²	4.819
xy	1.632
xz	0.000
yz	0.000

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

	x	y	z
x	3.042	-0.017	0.000
y	-0.017	3.139	0.000
z	0.000	0.000	3.170

<r²> (average value of r²) Å²

<r²>	80.905
(<r²>)^1/2	8.995

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

using model chemistry: mPW1PW91/3-21G*

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: mPW1PW91/3-21G*

States and conformations

Conformer 1 (C2H anti)

Conformer 2 (C2 gauche)

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