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

using model chemistry: BLYP/cc-pVDZ

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 BLYP/cc-pVDZ
 hartrees
Energy at 0K-578.863356
Energy at 298.15K-578.861983
Nuclear repulsion energy44.648176
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 BLYP/cc-pVDZ
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 457 458 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 228.5 cm-1
Scaled (by 1.0016) Zero Point Vibrational Energy (zpe) 228.8 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 BLYP/cc-pVDZ
B
0.22332

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.162
Si2 0.000 0.000 -1.162

Atom - Atom Distances (Å)
  Si1 Si2
Si12.3230
Si22.3230

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 BLYP/cc-pVDZ 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 -25.638 0.000 0.000
y 0.000 -25.638 0.000
z 0.000 0.000 -31.928
Traceless
 xyz
x 3.145 0.000 0.000
y 0.000 3.145 0.000
z 0.000 0.000 -6.290
Polar
3z2-r2-12.581
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 9.888 0.000 0.000
y 0.000 9.888 0.000
z 0.000 0.000 15.765


<r2> (average value of r2) Å2
<r2> 55.098
(<r2>)1/2 7.423

State 2 (1Σg)

Jump to S1C1
Energy calculated at BLYP/cc-pVDZ
 hartrees
Energy at 0K-578.826262
Energy at 298.15K-578.824975
Nuclear repulsion energy49.418698
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 BLYP/cc-pVDZ
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 574 575 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 286.8 cm-1
Scaled (by 1.0016) Zero Point Vibrational Energy (zpe) 287.2 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 BLYP/cc-pVDZ
B
0.27359

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

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.049
Si2 0.000 0.000 -1.049

Atom - Atom Distances (Å)
  Si1 Si2
Si12.0988
Si22.0988

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 BLYP/cc-pVDZ 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 -29.185 0.000 0.000
y 0.000 -29.185 0.000
z 0.000 0.000 -17.521
Traceless
 xyz
x -5.832 0.000 0.000
y 0.000 -5.832 0.000
z 0.000 0.000 11.665
Polar
3z2-r223.329
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 -3.715 0.000 0.000
y 0.000 -3.715 0.000
z 0.000 0.000 13.525


<r2> (average value of r2) Å2
<r2> 46.634
(<r2>)1/2 6.829