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

using model chemistry: BLYP/6-311G*

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/6-311G*
 hartrees
Energy at 0K-578.874935
Energy at 298.15K-578.873552
Nuclear repulsion energy44.638819
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/6-311G*
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 447 446 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 223.4 cm-1
Scaled (by 0.9975) Zero Point Vibrational Energy (zpe) 222.8 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/6-311G*
B
0.22322

See section I.F.4 to change rotational constant units
Geometric Data calculated at BLYP/6-311G*

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
Si12.3235
Si22.3235

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/6-311G* 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 -25.809 0.000 0.000
y 0.000 -25.809 0.000
z 0.000 0.000 -33.150
Traceless
 xyz
x 3.670 0.000 0.000
y 0.000 3.670 0.000
z 0.000 0.000 -7.340
Polar
3z2-r2-14.681
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 16.186 0.000 0.000
y 0.000 16.186 0.000
z 0.000 0.000 17.266


<r2> (average value of r2) Å2
<r2> 55.440
(<r2>)1/2 7.446

State 2 (1Σg)

Jump to S1C1
Energy calculated at BLYP/6-311G*
 hartrees
Energy at 0K-578.842768
Energy at 298.15K-578.841482
Nuclear repulsion energy49.822681
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/6-311G*
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 578 576 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 288.8 cm-1
Scaled (by 0.9975) Zero Point Vibrational Energy (zpe) 288.1 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 BLYP/6-311G*
B
0.27808

See section I.F.4 to change rotational constant units
Geometric Data calculated at BLYP/6-311G*

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Si1 0.000 0.000 1.041
Si2 0.000 0.000 -1.041

Atom - Atom Distances (Å)
  Si1 Si2
Si12.0818
Si22.0818

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/6-311G* 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 -29.573 0.000 0.000
y 0.000 -29.573 0.000
z 0.000 0.000 -18.427
Traceless
 xyz
x -5.573 0.000 0.000
y 0.000 -5.573 0.000
z 0.000 0.000 11.145
Polar
3z2-r222.291
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 -16.995 0.000 0.000
y 0.000 -16.995 0.000
z 0.000 0.000 14.347


<r2> (average value of r2) Å2
<r2> 46.486
(<r2>)1/2 6.818