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All results from a given calculation for SiH2F2 (difluorosilane)

using model chemistry: QCISD/3-21G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes C2V 1A1
Energy calculated at QCISD/3-21G
 hartrees
Energy at 0K-486.774143
Energy at 298.15K 
HF Energy-486.472252
Nuclear repulsion energy115.500025
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 QCISD/3-21G
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 A1 2282 2211 79.78      
2 A1 969 939 215.10      
3 A1 881 854 3.91      
4 A1 333 322 26.57      
5 A2 775 751 0.00      
6 B1 2287 2216 179.73      
7 B1 747 724 189.20      
8 B2 1080 1046 328.22      
9 B2 945 916 4.50      

Unscaled Zero Point Vibrational Energy (zpe) 5148.5 cm-1
Scaled (by 0.9692) Zero Point Vibrational Energy (zpe) 4989.9 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 QCISD/3-21G
ABC
0.73882 0.24969 0.20031

See section I.F.4 to change rotational constant units
Geometric Data calculated at QCISD/3-21G

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 0.478
F2 0.000 1.302 -0.516
F3 0.000 -1.302 -0.516
H4 1.237 0.000 1.301
H5 -1.237 0.000 1.301

Atom - Atom Distances (Å)
  Si1 F2 F3 H4 H5
Si11.63821.63821.48621.4862
F21.63822.60432.55522.5552
F31.63822.60432.55522.5552
H41.48622.55522.55522.4749
H51.48622.55522.55522.4749

picture of difluorosilane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
F2 Si1 F3 105.287 F2 Si1 H4 109.639
F2 Si1 H5 109.639 F3 Si1 H4 109.639
F3 Si1 H5 109.639 H4 Si1 H5 112.731
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability