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All results from a given calculation for SiH2F2 (difluorosilane)

using model chemistry: PBEPBE/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 PBEPBE/3-21G
 hartrees
Energy at 0K-487.485072
Energy at 298.15K 
HF Energy-487.485072
Nuclear repulsion energy114.232235
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 PBEPBE/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 2208 2188 86.75 156.80 0.10 0.18
2 A1 910 902 144.31 26.15 0.54 0.70
3 A1 827 820 4.40 10.14 0.37 0.54
4 A1 311 309 15.79 1.47 0.75 0.85
5 A2 733 727 0.00 21.24 0.75 0.86
6 B1 2216 2196 210.60 50.16 0.75 0.86
7 B1 700 693 118.46 8.60 0.75 0.86
8 B2 1023 1014 216.03 5.71 0.75 0.86
9 B2 887 879 0.19 9.85 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 4908.0 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 4863.4 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 PBEPBE/3-21G
ABC
0.72157 0.24448 0.19586

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 0.484
F2 0.000 1.316 -0.523
F3 0.000 -1.316 -0.523
H4 1.245 0.000 1.320
H5 -1.245 0.000 1.320

Atom - Atom Distances (Å)
  Si1 F2 F3 H4 H5
Si11.65691.65691.49951.4995
F21.65692.63252.58402.5840
F31.65692.63252.58402.5840
H41.49952.58402.58402.4893
H51.49952.58402.58402.4893

picture of difluorosilane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
F2 Si1 F3 105.199 F2 Si1 H4 109.801
F2 Si1 H5 109.801 F3 Si1 H4 109.801
F3 Si1 H5 109.801 H4 Si1 H5 112.203
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBE/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 Si 0.985      
2 F -0.336      
3 F -0.336      
4 H -0.156      
5 H -0.156      


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 1.711 1.711
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -23.295 0.000 0.000
y 0.000 -26.565 0.000
z 0.000 0.000 -23.554
Traceless
 xyz
x 1.765 0.000 0.000
y 0.000 -3.140 0.000
z 0.000 0.000 1.376
Polar
3z2-r22.751
x2-y23.270
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.938 0.000 0.000
y 0.000 2.650 0.000
z 0.000 0.000 2.806


<r2> (average value of r2) Å2
<r2> 61.246
(<r2>)1/2 7.826