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All results from a given calculation for C2 (Carbon diatomic)

using model chemistry: HF/STO-3G

19 10 17 12 22

States and conformations

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

State 1 (1Σg+)

Jump to S2C1
Energy calculated at HF/STO-3G
 hartrees
Energy at 0K-74.422201
Energy at 298.15K-74.419176
HF Energy-74.422201
Nuclear repulsion energy15.446118
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/STO-3G
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 2214 1808 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 1107.1 cm-1
Scaled (by 0.8165) Zero Point Vibrational Energy (zpe) 903.9 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/STO-3G
B
1.84704

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/STO-3G

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.617
C2 0.000 0.000 -0.617

Atom - Atom Distances (Å)
  C1 C2
C11.2333
C21.2333

picture of Carbon diatomic state 1 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/STO-3G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.000      
2 C 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 -10.422 0.000 0.000
y 0.000 -10.422 0.000
z 0.000 0.000 -7.810
Traceless
 xyz
x -1.306 0.000 0.000
y 0.000 -1.306 0.000
z 0.000 0.000 2.612
Polar
3z2-r25.225
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 -94.336 0.000 0.000
y 0.000 -94.336 0.000
z 0.000 0.000 3.873


<r2> (average value of r2) Å2
<r2> 10.529
(<r2>)1/2 3.245

State 2 (3Πu)

Jump to S1C1
Energy calculated at HF/STO-3G
 hartrees
Energy at 0K-74.498454
Energy at 298.15K-74.495427
HF Energy-74.498454
Nuclear repulsion energy14.678895
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/STO-3G
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 1975 1613 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 987.6 cm-1
Scaled (by 0.8165) Zero Point Vibrational Energy (zpe) 806.4 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 HF/STO-3G
B
1.66811

See section I.F.4 to change rotational constant units
Geometric Data calculated at HF/STO-3G

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
C1 0.000 0.000 0.649
C2 0.000 0.000 -0.649

Atom - Atom Distances (Å)
  C1 C2
C11.2978
C21.2978

picture of Carbon diatomic state 2 conformation 1
More geometry information
Electronic energy levels
Charges, Dipole, Quadrupole and Polarizability
Charges from optimized geometry at HF/STO-3G Charges (e)
Number Element Mulliken CHELPG AIM ESP
1 C 0.000      
2 C 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 -8.955 0.000 0.000
y 0.000 -10.416 0.000
z 0.000 0.000 -10.910
Traceless
 xyz
x 1.708 0.000 0.000
y 0.000 -0.483 0.000
z 0.000 0.000 -1.224
Polar
3z2-r2-2.449
x2-y21.460
xy0.000
xz0.000
yz0.000


Polarizabilities
Components of the polarizability tensor.
Units are Å3 (Angstrom cubed)
Change units.
  x y z
x 0.855 0.000 0.000
y 0.000 -0.883 0.000
z 0.000 0.000 2.856


<r2> (average value of r2) Å2
<r2> 11.357
(<r2>)1/2 3.370