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All results from a given calculation for Al2 (Aluminum diatomic)

using model chemistry: MP2/6-31G**

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 MP2/6-31G**
 hartrees
Energy at 0K-483.813839
Energy at 298.15K-483.813494
HF Energy-483.726318
Nuclear repulsion energy36.078879
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 MP2/6-31G**
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 362 339 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 180.9 cm-1
Scaled (by 0.9365) Zero Point Vibrational Energy (zpe) 169.4 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 MP2/6-31G**
B
0.20337

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31G**

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Al1 0.000 0.000 1.239
Al2 0.000 0.000 -1.239

Atom - Atom Distances (Å)
  Al1 Al2
Al12.4788
Al22.4788

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

Electronic state

Charges, Dipole, Quadrupole and Polarizability

State 2 (1Σg)

Jump to S1C1
Energy calculated at MP2/6-31G**
 hartrees
Energy at 0K-483.797038
Energy at 298.15K-483.796541
Nuclear repulsion energy30.147108
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 MP2/6-31G**
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 236 221 0.00      

Unscaled Zero Point Vibrational Energy (zpe) 118.2 cm-1
Scaled (by 0.9365) Zero Point Vibrational Energy (zpe) 110.7 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 MP2/6-31G**
B
0.14200

See section I.F.4 to change rotational constant units
Geometric Data calculated at MP2/6-31G**

Point Group is D∞h

Cartesians (Å)
Atom x (Å) y (Å) z (Å)
Al1 0.000 0.000 1.483
Al2 0.000 0.000 -1.483

Atom - Atom Distances (Å)
  Al1 Al2
Al12.9665
Al22.9665

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

Electronic state

Charges, Dipole, Quadrupole and Polarizability