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

using model chemistry: B3LYP/LANL2DZ

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 B3LYP/LANL2DZ
 hartrees
Energy at 0K-7.623231
Energy at 298.15K-7.621845
Nuclear repulsion energy3.599060
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 B3LYP/LANL2DZ
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 446 428 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 222.8 cm-1
Scaled (by 0.9612) Zero Point Vibrational Energy (zpe) 214.1 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 B3LYP/LANL2DZ
B
0.21775

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/LANL2DZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.176
Si2 0.000 0.000 -1.176

Atom - Atom Distances (Å)
  Si1 Si2
Si12.3525
Si22.3525

picture of Silicon diatomic state 1 conformation 1
More geometry information
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/LANL2DZ 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 -23.336 0.000 0.000
y 0.000 -23.336 0.000
z 0.000 0.000 -32.163
Traceless
 xyz
x 4.413 0.000 0.000
y 0.000 4.413 0.000
z 0.000 0.000 -8.827
Polar
3z2-r2-17.654
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 44.130 0.000 0.000
y 0.000 44.130 0.000
z 0.000 0.000 15.996


<r2> (average value of r2) Å2
<r2> 27.482
(<r2>)1/2 5.242

State 2 (1Σg)

Jump to S1C1
Energy calculated at B3LYP/LANL2DZ
 hartrees
Energy at 0K-7.597720
Energy at 298.15K-7.596325
Nuclear repulsion energy3.568095
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 B3LYP/LANL2DZ
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 436 419 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 218.0 cm-1
Scaled (by 0.9612) Zero Point Vibrational Energy (zpe) 209.5 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 B3LYP/LANL2DZ
B
0.21402

See section I.F.4 to change rotational constant units
Geometric Data calculated at B3LYP/LANL2DZ

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.186
Si2 0.000 0.000 -1.186

Atom - Atom Distances (Å)
  Si1 Si2
Si12.3729
Si22.3729

picture of Silicon diatomic state 2 conformation 1
More geometry information
Electronic energy levels

Electronic state

Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at B3LYP/LANL2DZ 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 -28.317 0.000 0.000
y 0.000 -18.729 0.000
z 0.000 0.000 -32.046
Traceless
 xyz
x -2.930 0.000 0.000
y 0.000 11.453 0.000
z 0.000 0.000 -8.523
Polar
3z2-r2-17.046
x2-y2-9.589
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 3.185 0.000 0.000
y 0.000 11.023 0.000
z 0.000 0.000 15.542


<r2> (average value of r2) Å2
<r2> 27.728
(<r2>)1/2 5.266