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All results from a given calculation for SiC2 (Silicon dicarbide)

using model chemistry: PBEPBEultrafine/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 PBEPBEultrafine/3-21G
 hartrees
Energy at 0K-363.301496
Energy at 298.15K 
HF Energy-363.301496
Nuclear repulsion energy60.758373
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 PBEPBEultrafine/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 1686 1671 12.24 24.50 0.08 0.15
2 A1 740 734 106.68 35.05 0.39 0.56
3 B2 106 106 60.10 11.92 0.75 0.86

Unscaled Zero Point Vibrational Energy (zpe) 1266.3 cm-1
Scaled (by 0.9909) Zero Point Vibrational Energy (zpe) 1254.8 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 PBEPBEultrafine/3-21G
ABC
1.67249 0.39480 0.31940

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

Point Group is C2v

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 0.839
C2 0.000 0.648 -0.979
C3 0.000 -0.648 -0.979

Atom - Atom Distances (Å)
  Si1 C2 C3
Si11.93011.9301
C21.93011.2961
C31.93011.2961

picture of Silicon dicarbide state 1 conformation 1
More geometry information
Calculated Bond Angles
atom1 atom2 atom3 angle atom1 atom2 atom3 angle
C2 Si1 C3 39.237
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at PBEPBEultrafine/3-21G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 Si 0.569      
2 C -0.285      
3 C -0.285      


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 2.199 2.199
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -23.232 0.000 0.000
y 0.000 -26.491 0.000
z 0.000 0.000 -26.079
Traceless
 xyz
x 3.053 0.000 0.000
y 0.000 -1.835 0.000
z 0.000 0.000 -1.217
Polar
3z2-r2-2.435
x2-y23.259
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.865 0.000 0.000
y 0.000 5.668 0.000
z 0.000 0.000 7.100


<r2> (average value of r2) Å2
<r2> 42.179
(<r2>)1/2 6.495