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

using model chemistry: HF/6-31G

19 10 17 12 22

States and conformations

State Conformation minimum conformation conformer description state description
1 1 yes D*H 3Σg
2 1 yes D*H 1Σg

State 1 (3Σg)

Jump to S2C1
Energy calculated at HF/6-31G
 hartrees
Energy at 0K-577.683926
Energy at 298.15K-577.682592
Nuclear repulsion energy44.868134
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 HF/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 Σg 507 458 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 253.7 cm-1
Scaled (by 0.9029) Zero Point Vibrational Energy (zpe) 229.1 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 HF/6-31G
B
0.22552

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.156
Si2 0.000 0.000 -1.156

Atom - Atom Distances (Å)
  Si1 Si2
Si12.3116
Si22.3116

picture of Silicon diatomic state 1 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/6-31G 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 -26.852 0.000 0.000
y 0.000 -26.852 0.000
z 0.000 0.000 -37.391
Traceless
 xyz
x 5.270 0.000 0.000
y 0.000 5.270 0.000
z 0.000 0.000 -10.539
Polar
3z2-r2-21.078
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 17.095 0.000 0.000
y 0.000 17.095 0.000
z 0.000 0.000 20.176


<r2> (average value of r2) Å2
<r2> 52.342
(<r2>)1/2 7.235

State 2 (1Σg)

Jump to S1C1
Energy calculated at HF/6-31G
 hartrees
Energy at 0K-577.606720
Energy at 298.15K-577.605422
Nuclear repulsion energy48.568376
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 HF/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 Σg 560 506 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 280.0 cm-1
Scaled (by 0.9029) Zero Point Vibrational Energy (zpe) 252.8 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 HF/6-31G
B
0.26425

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.068
Si2 0.000 0.000 -1.068

Atom - Atom Distances (Å)
  Si1 Si2
Si12.1355
Si22.1355

picture of Silicon diatomic state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/6-31G 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 -31.282 0.000 0.000
y 0.000 -31.282 0.000
z 0.000 0.000 -19.066
Traceless
 xyz
x -6.108 0.000 0.000
y 0.000 -6.108 0.000
z 0.000 0.000 12.216
Polar
3z2-r224.433
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 -2.646 0.000 0.000
y 0.000 -2.646 0.000
z 0.000 0.000 15.549


<r2> (average value of r2) Å2
<r2> 48.918
(<r2>)1/2 6.994