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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-487.614127
Energy at 298.15K 
HF Energy-487.614127
Nuclear repulsion energy117.259856
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
(Å4/u)
Dep P Dep U
1 A1 2262 2157 71.42 129.22 0.11 0.20
2 A1 967 922 169.69 17.28 0.46 0.63
3 A1 884 843 2.18 8.91 0.52 0.69
4 A1 325 310 14.58 0.92 0.75 0.86
5 A2 752 717 0.00 14.70 0.75 0.86
6 B1 2268 2162 196.88 35.62 0.75 0.86
7 B1 724 690 127.42 5.94 0.75 0.86
8 B2 1081 1031 241.39 1.47 0.75 0.86
9 B2 922 879 8.80 9.67 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 5091.9 cm-1
Scaled (by 0.9535) Zero Point Vibrational Energy (zpe) 4855.1 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
0.78572 0.25293 0.20583

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 0.456
F2 0.000 1.293 -0.497
F3 0.000 -1.293 -0.497
H4 1.241 0.000 1.285
H5 -1.241 0.000 1.285

Atom - Atom Distances (Å)
  Si1 F2 F3 H4 H5
Si11.60661.60661.49191.4919
F21.60662.58652.52722.5272
F31.60662.58652.52722.5272
H41.49192.52722.52722.4811
H51.49192.52722.52722.4811

picture of difluorosilane state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
F2 Si1 F3 107.214 F2 Si1 H4 109.243
F2 Si1 H5 109.243 F3 Si1 H4 109.243
F3 Si1 H5 109.243 H4 Si1 H5 112.513
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 0.720      
2 F -0.256      
3 F -0.256      
4 H -0.104      
5 H -0.104      


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 1.126 1.126
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -22.871 0.000 0.000
y 0.000 -25.207 0.000
z 0.000 0.000 -22.914
Traceless
 xyz
x 1.190 0.000 0.000
y 0.000 -2.315 0.000
z 0.000 0.000 1.125
Polar
3z2-r22.250
x2-y22.337
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 2.821 0.000 0.000
y 0.000 2.494 0.000
z 0.000 0.000 2.648


<r2> (average value of r2) Å2
<r2> 58.624
(<r2>)1/2 7.657