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All results from a given calculation for Si2 (Silicon diatomic)

using model chemistry: B1B95/cc-pVQZ

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
2 1 yes D*H 1Σg

State 1 (3Σg)

Jump to S2C1
Vibrational Frequencies calculated at B1B95/cc-pVQZ
Rotational Constants (cm-1) from geometry optimized at B1B95/cc-pVQZ
See section I.F.4 to change rotational constant units
Geometric Data calculated at B1B95/cc-pVQZ
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability

State 2 (1Σg)

Jump to S1C1
Energy calculated at B1B95/cc-pVQZ
 hartrees
Energy at 0K-578.900087
Energy at 298.15K-578.898826
Nuclear repulsion energy50.696867
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 B1B95/cc-pVQZ
Mode Number Symmetry Frequency
(cm-1)
Scaled Frequency
(cm-1)
IR Intensities
(km mol-1)
Raman Act
4/u)
Dep P Dep U
1 Σg 617 617 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 308.4 cm-1
Scaled (by 1) Zero Point Vibrational Energy (zpe) 308.4 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 B1B95/cc-pVQZ
B
0.28792

See section I.F.4 to change rotational constant units
Geometric Data calculated at B1B95/cc-pVQZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.023
Si2 0.000 0.000 -1.023

Atom - Atom Distances (Å)
  Si1 Si2
Si12.0459
Si22.0459

picture of Silicon diatomic state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B1B95/cc-pVQZ Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 Si 0.000      
2 Si 0.000      


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 0.000 0.000
CHELPG        
AIM        
ESP        


Electric Quadrupole moment
Quadrupole components in D Å
Primitive
 xyz
x -29.275 0.000 0.000
y 0.000 -29.275 0.000
z 0.000 0.000 -17.379
Traceless
 xyz
x -5.948 0.000 0.000
y 0.000 -5.948 0.000
z 0.000 0.000 11.897
Polar
3z2-r223.793
x2-y20.000
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 53.953 0.000 0.000
y 0.000 53.953 0.000
z 0.000 0.000 14.326


<r2> (average value of r2) Å2
<r2> 45.107
(<r2>)1/2 6.716