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All results from a given calculation for SiH2F2 (difluorosilane)

using model chemistry: QCISD/6-31G*

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/6-31G*
 hartrees
Energy at 0K-489.521081
Energy at 298.15K 
HF Energy-489.080724
Nuclear repulsion energy117.477145
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/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 A1 2343 2231 74.01      
2 A1 1011 963 179.95      
3 A1 884 842 48.63      
4 A1 323 308 20.08      
5 A2 763 726 0.00      
6 B1 2355 2242 192.68      
7 B1 739 704 152.77      
8 B2 1042 992 347.65      
9 B2 929 884 0.41      

Unscaled Zero Point Vibrational Energy (zpe) 5194.1 cm-1
Scaled (by 0.9523) Zero Point Vibrational Energy (zpe) 4946.3 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 QCISD/6-31G*
ABC
0.80263 0.25138 0.20590

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 0.452
F2 0.000 1.297 -0.491
F3 0.000 -1.297 -0.491
H4 1.239 0.000 1.260
H5 -1.239 0.000 1.260

Atom - Atom Distances (Å)
  Si1 F2 F3 H4 H5
Si11.60421.60421.47911.4791
F21.60422.59502.50702.5070
F31.60422.59502.50702.5070
H41.47912.50702.50702.4783
H51.47912.50702.50702.4783

picture of difluorosilane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
F2 Si1 F3 107.963 F2 Si1 H4 108.729
F2 Si1 H5 108.729 F3 Si1 H4 108.729
F3 Si1 H5 108.729 H4 Si1 H5 113.810
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability