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

using model chemistry: CCD/6-31G*

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 no C2H anti 1Ag
1 2 yes C2 gauche 1A

Conformer 1 (C2H anti)

Jump to S1C2
Energy calculated at CCD/6-31G*
 hartrees
Energy at 0K-277.540915
Energy at 298.15K 
HF Energy-276.920628
Nuclear repulsion energy125.478594
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 CCD/6-31G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Ag 3108 2941 0.00      
2 Ag 1580 1496 0.00      
3 Ag 1510 1429 0.00      
4 Ag 1133 1073 0.00      
5 Ag 1120 1060 0.00      
6 Ag 470 445 0.00      
7 Au 3179 3009 60.91      
8 Au 1263 1196 3.54      
9 Au 835 790 0.17      
10 Au 139 132 13.69      
11 Bg 3157 2988 0.00      
12 Bg 1329 1258 0.00      
13 Bg 1215 1150 0.00      
14 Bu 3112 2945 52.74      
15 Bu 1588 1503 2.25      
16 Bu 1394 1320 18.27      
17 Bu 1132 1072 177.02      
18 Bu 282 267 20.58      

Unscaled Zero Point Vibrational Energy (zpe) 13773.6 cm-1
Scaled (by 0.9465) Zero Point Vibrational Energy (zpe) 13036.7 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 CCD/6-31G*
ABC
1.05823 0.12926 0.12049

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCD/6-31G*

Point Group is C2h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.428 0.625 0.000
C2 -0.428 -0.625 0.000
F3 -0.428 1.724 0.000
F4 0.428 -1.724 0.000
H5 1.060 0.665 0.894
H6 1.060 0.665 -0.894
H7 -1.060 -0.665 0.894
H8 -1.060 -0.665 -0.894

Atom - Atom Distances (Å)
  C1 C2 F3 F4 H5 H6 H7 H8
C11.51511.39222.34881.09521.09522.16212.1621
C21.51512.34881.39222.16212.16211.09521.0952
F31.39222.34883.55172.03272.03272.62712.6271
F42.34881.39223.55172.62712.62712.03272.0327
H51.09522.16212.03272.62711.78732.50163.0745
H61.09522.16212.03272.62711.78733.07452.5016
H72.16211.09522.62712.03272.50163.07451.7873
H82.16211.09522.62712.03273.07452.50161.7873

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 107.704 C1 C2 H7 110.824
C1 C2 H8 110.824 C2 C1 F3 107.704
C2 C1 H5 110.824 C2 C1 H6 110.824
F3 C1 H5 109.032 F3 C1 H6 109.032
F4 C2 H7 109.032 F4 C2 H8 109.032
H5 C1 H6 109.376 H7 C2 H8 109.376
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

Conformer 2 (C2 gauche)

Jump to S1C1
Energy calculated at CCD/6-31G*
 hartrees
Energy at 0K-277.540945
Energy at 298.15K 
HF Energy-276.919902
Nuclear repulsion energy127.813560
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 CCD/6-31G*
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A 3149 2980 17.44      
2 A 3099 2933 33.83      
3 A 1561 1478 0.04      
4 A 1497 1417 20.43      
5 A 1331 1260 1.52      
6 A 1178 1115 7.35      
7 A 1169 1106 66.61      
8 A 916 867 24.42      
9 A 333 315 0.44      
10 A 147 140 3.62      
11 B 3161 2992 45.39      
12 B 3088 2923 14.33      
13 B 1560 1476 5.14      
14 B 1458 1380 13.65      
15 B 1289 1220 4.51      
16 B 1142 1081 35.63      
17 B 941 891 34.42      
18 B 510 483 17.60      

Unscaled Zero Point Vibrational Energy (zpe) 13764.2 cm-1
Scaled (by 0.9465) Zero Point Vibrational Energy (zpe) 13027.8 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 CCD/6-31G*
ABC
0.56445 0.17064 0.14799

See section I.F.4 to change rotational constant units
Geometric Data calculated at CCD/6-31G*

Point Group is C2

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.266 0.704 0.521
C2 -0.266 -0.704 0.521
F3 -0.266 1.403 -0.556
F4 0.266 -1.403 -0.556
H5 -0.020 1.220 1.447
H6 1.358 0.700 0.427
H7 0.020 -1.220 1.447
H8 -1.358 -0.700 0.427

Atom - Atom Distances (Å)
  C1 C2 F3 F4 H5 H6 H7 H8
C11.50571.38982.36661.09751.09572.14942.1486
C21.50572.36661.38982.14942.14861.09751.0957
F31.38982.36662.85602.02612.02413.31252.5649
F42.36661.38982.85603.31252.56492.02612.0241
H51.09752.14942.02613.31251.79162.44022.5523
H61.09572.14862.02412.56491.79162.55233.0547
H72.14941.09753.31252.02612.44022.55231.7916
H82.14861.09572.56492.02412.55233.05471.7916

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 109.574 C1 C2 H7 110.325
C1 C2 H8 110.373 C2 C1 F3 109.574
C2 C1 H5 110.325 C2 C1 H6 110.373
F3 C1 H5 108.518 F3 C1 H6 108.465
F4 C2 H7 108.518 F4 C2 H8 108.465
H5 C1 H6 109.541 H7 C2 H8 109.541
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability